class-11 - edusys 11 / 5 eduheal foundation angle between pair of lines through the origin, combined...

Class-11

CLASS ‐ XI S. No. Topic Page No.

1. Syllabus Guide Line 04

2. Biotechnology 13

3. All About Cloning 20

4. The Genetic Recipe for Making Proteins 26

5. 30 New Mutations per Lifetime 27

6. What is Gene Testing? 28

7. What is Gene Therapy? 29

8. Small Machine to Tackle Big Deals 31

9. DNA Fingerprinting 33

10. Blood From a Plant 44

11. What is Phytoremediation? 45

12. Some of the Exciting Careers in Biotechnology 47

13. Biotechnology and Biodiversity 48

4 / Class 11 E d u h e a l F o u n d a tio n

CLASS XI & XII Key Topics in Mathematics for Class XI and XII

I. ALGEBRA

1. Sets, Relations and Functions : Sets and their Representations, Union, intersection and complements of sets, and their algebraic properties, Relations, equivalence relations, mappings, oneone, into and onto mappings, composition of mappings

2 . Complex Numbers : Complex number in the form a + ib and their representation in a plane. Argand diagram. Algebra of complex numbers, Modulous and Arguments (or amplitude) of a complex number, square root of a complex number. Cube roots of unity, triangle – inequality.

3 . Matrices and Determinants : Determinants and matrices of order two and three, properties of determinants, Evaluation of determinants. Area of triangles using determinants, Addition and multiplication of matrices, adjoint and inverse of matrix. Test of consistency and solution of simultaneous linear equations using determinants and matrices.

4 . Quadratic Equations : Quadratic equation in real and complex number system and their solutions. Relation between roots and coefficients, nature of roots, formation of quadratic equations with given roots; Symmetric functions of roots.

5 . Permutation and Combination : Fundamental principle of counting; Permutation as an arrangement. Meaning of P(n, r) and C (n , r). Simple applications.

6 . Mathematical Induction and Its applications :

7 . Binomial Theorem and its Applications : Binomial Theorem for a positive integral index; general term and middle term; Binomial Theorem for any index. Properties of Binomial Coefficients. Simple applications for approximations.

8 . Sequences and Series : Arithmetic, Geometric and Harmonic progressions. Special cases of Sn , Sn2, Sn3 . Arithmetic Geometric Series, Exponential and Logarithmic series.

II. CALCULUS

9. Differential Calculus : Polynomials, rational, trigonometric, logarithmic and exponential functions, Inverse functions. Graphs of simple functions. Limits, Continuity; differentiation of the sum, difference, product and quotient of two functions. differentiation of trigonometric, inverse trigonometric, logarithmic, exponential, composite and implicit functions; derivatives of order upto three. Applications of derivative: monotonic functions, Maxima and minima of functions of one variable.

10 . Integral Calculus : Integral as an antiderivative. Fundamental integrals involving algebraic, trigonometric, exponential and logarithmic functions. Integration by substitution, by parts and by partial fractions. Integration using trigonometric identities. Integral as limit of a sum. Properties of definite integrals. Evaluation of indefinite integrals; Determining areas of the regions bounded by simple curves.

11. Differential Equations : Ordinary differential equations, their order and degree. Solution of differential equations by the method of separation of variables. Solution of homogeneous and linear differential equations.

III. TWO AND THREE DIMENSIONAL GEOMETRY

12. Two dimensional Geometry : Recall of Cartesian system of Rectangular coordinates in a plane, distance formula, area of a triangle, condition for the collinearity of three points and section formula, centroid and incentre of a triangle, locus and its equation, translation of axes, slope of a line, parallel and perpendicular lines, intercepts of a line on the coordinate axes. The straight line and pair of straight lines Various forms of equations of a line, intersection of lines, angles between two lines, conditions for concurrency of three lines, distance of point from a line, coordinates of orthocentre and circumcentre of triangle, equation of family of lines passing through the point of intersection of two lines, homogeneous equation of second degree in x and y,

Statements given in italics are related to biotechnology. The syllabus guideline given is only indicative & not exhaustive.

Class 11 / 5 E d u h e a l F o u n d a tio n

angle between pair of lines through the origin, combined equation of the bisectors of the angles between a pair of lines, condition for the general second degree equation to represent a pair of lines, point of intersection and angle between two lines represented by S = O and the factors of S .

Circles and system of Circles Standard form of equation of a circle, general form of the equation of a circle, its radius and centre, equation of a circle in the parametric form, equation of a circle when the end points of a diameter are given, points of intersection of a line and a circle with the centre at the origin and condition for a line to be tangent to the circle, length of the tangent, equation of the tangent, equation of a family of circles through the intersection of two circles, condition for two intersecting circles to be orthogonal.

Conic Section Sections of cones, equations of conic sections (parabola, ellipse and hyperbola) in standard forms, condition for y = mx + c to be a tangent and point(s) of tangency.

13 . Three dimensional Geometry : Coordinates of a point in space, distance between the points; Section formula, direction ratios and direction cosines, angle between two intersecting lines, equations of a line and a plane in different forms; intersection of a line and a plane, coplanar lines, equation of a sphere, its centre and radius. Diameter form of the equation of a sphere.

IV. VECTORS

14. Vector Algebra : Vectors and Scalars, addition of vectors, components of a vector in two dimensions and three dimensional space, scalar and vector products, vector triple product. Application of vectors to plane geometry.

V. STATISTICS

15. Measures of Central Tendency and Dispersion : Calculation of Mean, median and mode of grouped and ungrouped data. Calculation of standard deviation, variance and mean deviation for grouped and ungrouped data.

16 . Probability : Probability of an event, addition and multiplication theorems of probability and their applications; Conditional probability; Probability distribution of a random variable; Binomial distribution and its properties.

VI. TRIGONOMETRY

17. Trigonometrical ratios, identities and equations. Inverse trigonometric functions and their properties. Properties of triangles, solution of triangles. Heights and Distances.

VII. STATICS AND DYNAMICS

18. Statics : Resultant of Coplanar forces; moments and couples. Equilibrium of three concurrent forces.

19 . Dynamics : Speed and velocity, average speed, instantaneous speed, acceleration and retardation, resultant of two velocities, relative velocity and its simple applications. Motion of a particle along a line, moving with constant

acceleration. Motion under gravity. Laws of motion, Projectile motion.

Key Topics in Physics for Class XI and XII 1 . Units and Measurement : Units for measurement, system of units – S.I., fundamental and derived units. Dimensions

and their applications.

2 . Description of Motion in one dimension : Motion in a straight line, uniform motion, its graphical representation. Uniformly accelerated motion, and its applications.

3 . Description of Motion in Two and Three dimensions : Scalars and vectors, vector addition, multiplication of a vector by a real number, zerovector and its properties. Resolution of vectors. Scalar and vector products, uniform circular motion and its applications, projectile motion.

4 . Laws of Motion : Force and inertia – Newton’s Laws of motion. Conservation of linear momentum, rocket propulsion. Inertial frames of references. Static and kinetic friction, laws of friction, rolling friction.<O:P

5 . Work, Energy and Power : Concept of work, energy and power, Energy – kinetic and potential. Conservation of energy. Elastic collision in one and two dimensions. Different forms of energy.

6 . Rotational Motion and Moment of Inertia : Centre of mass of a twoparticle system. Centre of mass of a rigid body, general motion of a rigid body, nature of rotational motion, torque, angular momentum, conservation of angular


momentum and its applications. Moment of Inertia and its physical significance, parallel and perpendicular axes theorem, expression of moment of inertia for ring, disc and sphere.

7 . Gravitation : Acceleration due to gravity, one and twodimensional motion under gravity. Universal law of gravitation, variation in the acceleration due to gravity of the earth. Planetary motion, artificial satellite – geostationary satellite, gravitational potential energy near the surface of earth, gravitational potential and escape velocity.

8 . Properties of Matter : Interatomic and intermolecular forces, states of matter (A) Solids : Elastic properties, Hook’s law, Young’s modulus, bulk modulus, modulus of rigidity. (B) Liquids : Cohesion and adhesion. Surface energy and surface tension. Flow of fluids, Bernoulli’s theorem and its applications. Viscosity, Stoke’s Law, terminal velocity. (C) Ideal gas laws.

9 . Oscillations : Periodic motion, simple harmonic motion and its equation of motion, energy in S.H.M., Oscillations of a spring and simple pendulum.

10 . Waves : Wave motion, speed of a wave, longitudinal and transverse waves, superposition of waves, progressive and standing waves, vibration of strings and aircolumns, beats, resonance. Doppler effect in sound.

11. Heat and Thermodynamics : Thermal expansion of solids, liquids and gases and their specific heats, relationship between C p and C v for gases, first law of thermodynamics, thermodynamic processes. Second law of thermodynamics, Carnot cycle, efficiency of heat engines.

12 . Transference of heat : Modes of transference of heat. Thermal conductivity. Black body radiations, Kirchoff’s law, Wien’s law, Stefan’s law of radiation and Newton’s law of cooling.

13 . Electrostatics : Charges and their conservation, Coulomb’s law, S.I. unit of charge, dielectric constant, electric field, lines of force, field due to dipole and its behavior in a uniform electric field, electric flux, Gauss’s law in simple geometries. Electric potential, potential due to a point charge. Conductors and insulators, distribution of charge on conductors. Capacitance, parallel plate capacitor, combination of capacitors, energy of capacitor, van de graf generator.

14 . Current Electricity : Current as a rate of flow of charges, sources of energy, cellsprimary and secondary, grouping of cells resistance of different materials, temperature dependence, specific resistance, Ohm’s law, Kirchoff’s law, series and parallel circuits. Wheatstone Bridge, measurement of voltages and currents, potentiometer.

15 . Thermal and Chemical Effects of currents : Heating effects of current, electric power, simple concept of thermo electricity – (Seeback effect and its explanation), thermocouple, Chemical effects of current and laws of electrolysis.

16 . Magnetic Effects of Currents : Oersted’s experiment, BiotSavert’s law (magnetic field due to a current element), magnetic field due to a straight wire, circular loop and solenoid, force on a moving charge in a uniform magnetic field (Lorentz force), forces and torques on currents in a magnetic field, force between two current carrying wires, moving coil galvanometer, ammeter and voltmeter.

17 . Magnetostatics : Bar magnet, magnetic field, lines of force, torque on a bar magnet in a magnetic field, earth’s magnetic field, tangent galvanometer, vibration magnetometer, para, dia and ferromagnetism, magnetic induction, magnetic susceptibility.

18 . Electromagnetic Induction and Alternating Currents : Induced e.m.f., Farady’s Law, Lenz’s Law, self and mutual induction, alternating currents, impedance and reactance, power in a.c. circuits, LCR series combination, resonant circuits. Transformer, simple motor, and A.C. generator.

19 . Ray Optics : Sources of light, luminous intensity, luminous flux, illuminance and photometry(elementary idea). Reflection and refraction of light at plane and curved surfaces, total internal reflection, optical fibre; deviation and dispersion of light by a prism; Lens formula, magnification and resolving power; microscope and telescope.

20 . Wave Optics : Wave nature of light; Interference – Young’s double slit experiment. Diffraction – diffraction due to a single slit. Elementary idea of polarization, Doppler effect of light.

21 . Electromagnetic waves : Electromagnetic oscillations, Electromagnetic wave spectrum from gamma to radio waves – their uses and propogation properties of the atmosphere w.r.t. electromagnetic spectrum.

22 . Electrons and Photons : Discovery of electrons, cathode rays, charge on an electron, e/m for an electron, photoelectric effect and Einstein’s equation of photoelectric effect.

23 . Atoms, Molecules and Nuclei : Rutherford model of the atom, Bohr’s model, energy quantizations, hydrogen spectrum; Atomic masses, size of the nucleus; Radioactivity; rays and their properties – alpha, beta and gamma decay;


half life and mean life of radioactive nuclei, Binding energy, mass energy relationship, nuclear fission and nuclear fusion. 24 . Solids and SemiConductor Devices : Energy bands in solids, conductors, insulators and semiconductors, PN

junction, diodes, diode as rectifier, junction transistor, transistor as an amplifier.

Key Topics in Chemistry for Class XI and XII

1 . Atoms, Molecules and Chemical Arithmetic : Measurement in chemistry (significant figures, SI unit, Dimensional analysis). Chemical classification of matter (mixtures, compounds and elements, and purification). Law of chemical combination and Dalton’s Atomic theory. Atomic Mass (mole concept, determination of chemical formulae). Chemical equation (balancing of chemical equation and calculations using chemical equations).

2 . Elements, their Occurrence and extraction : Earth as a source of elements, elements in biology, extraction of metals (mettallurgical process, production of concentrated ore, production of metals and their purification). Mineral wealth of India. Qualitative test of metals.

3 . States of Matter Gaseous state : (measurable properties of gases, Boyle’s Law, Charle’s Law and absolute scale of temperature, Avogadro’s hypothesis, ideal gas equation, Dalton’s law of partial pressure). Kinetic molecular theory of gases (the microscopic model of gas, deviation form ideal behaviour). The solid state (classification of solids, X ray studies of crystal lattices and unit cells, packing of constituent particles in crystals). Liquid state (Properties of liquids, Vapour pressure, Surface tension, Viscosity).

4 . Atomic Structures Constituents of the atom : (Discovery of electron, Rutherford model of the atom). Electronic structure of atoms (nature of light and electromagnetic waves, atomic spectra, Bohr’s model of Hydrogen atom, Quantum mechanical model of the atom, electronic configurations of atoms, Aufbau principle). Dual nature of matter and radiation. The uncertainty principle. Orbitals and Quantum numbers. Shapes of orbitals. Electronic configuration of atoms.

5 . Chemical Families – Periodic Properties : Mendeleev’s Periodic Table, Modern Periodic Law, Types of elements (Representative elementss & p block elements, inner transition elements – dblock elements, inner transition elements – fblock elements). Periodic trends in properties. (Ionization energy, electron affinity, atomic radii, valence, periodicity in properties of compounds).

6 . Chemical Bonding and Molecular structure : Chemical bonds and Lewis structure shapes of molecules (VSEPR theory). Quantum theory of the covalent bond (Hydrogen and some other simple molecules, carbon compounds, hybridization, Boron and Beryllium compounds). Coordinate covalent bond (Ionic bond as an extreme case of polar covalent bond, ionic character of molecules and polar molecules. Bonding in solid state (Ionic, molecular and covalent solids, metals). Hydrogen bond, Resonance. Molecules: Molecular orbital method. Formation of H 2 , O 2 , N 2 , F 2 on the basis of MOT. Hybridisation, Dipole moment and structure of molecules.

7 . The Solid State : Structure of simple ionic compounds. Closepacked structures. Ionicradii, Silicates (elementary ideas). Imperfection in solids (point defects only). Properties of solids, Amorphous solids. The Gaseous state : Ideal gas equationKinetic theory (fundamentals only)

8 . Solutions : Types of solutions, Vapourpressure of solutions and Raoult’s law. Colligative properties. Nonideal solutions and abnormal molecular masses. Mole conceptstoichemistry, volumetric analysisconcentration unit.<O:P

9 . Chemical Energetics and Thermodynamics : Energy changes during a chemical reaction, Internal energy and Enthalpy (Internal energy, Enthalpy, Enthalpy changes, Origin of Enthalpy change in a reaction, Hess’s Law of constant heat summation, numericals based on these concepts). Heats of reactions (heat of neutralization, heat of combustion, heat of fusion and vaporization). Sources of energy (conservation of energy sources and identification of alternative sources, pollution associated with consumption of fuels. The sun as the primary source). First law of thermodynamics: Internal energy, Enthalpy, application of first law of thermodynamics. Second law of thermodynamics : Entropy, Free energy, Spontaneity of a chemical reaction, free energy change and chemical equilibrium, free energy available for useful work.

10 . Chemical Equilibrium : Equilibria involving physical changes (solidliquid, liquidgas equilibrium involving dissolution of solid in liquids, gases in liquids, general characteristics of equilibrium involving physical processes). Equilibria involving chemical systems (the law of chemical equilibrium, the magnitude of the equilibrium constant, numerical problems). Effect of changing conditions of systems at equilibrium (change of concentration, change of temperature, effect of catalystLe Chateliar’s principle). Equilibria involving ions (ionization of electrolytes, weak and strong


electrolytes, acidbase equilibrium, various concepts of acids and bases, ionization of water, pH, solubility product, numericals based on these concepts).

11. Redox Reactions and Electrochemistry : Oxidation and reduction as an electron transfer process. Redox reactions in aqueous solutionselectrochemical cells. EMF of a galvanic cell. Dependence of EMF on concentration and temperature (nearest equation and numerical problems based on it). Electrolysis, Oxidation numbers (rules for assigning oxidation number, redox reactions in terms of oxidation number and nomenclature). Balancing of oxidationreduction equations. Electrolytic conduction. Voltaic cell, Electrode potential and Electromotive force, Gibb’s free energy and cell potential. Electrode potential and Electrolysis.

12 . Rates of Chemical Reactions and Chemical Kinetics : Rate of reaction, Instantaneous rate of reaction and order of reaction. Factors affecting rates of reactions (factors affecting rate of collisions encountered between the reactant molecules, effect of temperature on the reaction rate, concept of activation energy, catalysis). Effect of light on rates of reactions. Elementary reactions as steps to more complex reactions. How fast are chemical reactions?Rate expression. Order of a reaction (with suitable examples). Units of rates and specific rate constants. Order of reaction and effect of concentration. (study will be confined to first order only). Temperature dependence of rate constant – Fast reactions (only elementary idea). Mechanism of reaction (only elementary idea). Photochemical reactions.

13 . Chemistry of Hydrocarbons : Alkanes (structure, isomerism, conformation). Stereo Isomerism and chirality (origin of chirality, optical rotation, racemic mixture) Alkenes (isomerism including cistrans). Alkynes. Arenes (structure of benzene, resonance structure, isomerism in arenes). Sources of hydrocarbons (origin and composition of coal and petroleum; Hydrocarbons from coal and petroleum cracking and reforming, quality of gasolineoctane number, gasoline additives). Laboratory preparation of alkanes (preparation from unsaturated hydrocarbons, alkyl halides and carboxylic acids). Laboratory preparation of alkenes (preparation from alcohols, alkyl halides). Laboratory prepration of alkynes (preparation from calcium carbide and accetylene). Physical properties of alkanes( boiling and melting points, solubility and density). Reactions of hydrocarbons (oxidation, addition, substitution and miscellaneous reactions).

14 . Purification and Characterisation of Organic Compounds : Purification (crystallization, sublimation, distillation, differential extraction, chromatography). Qualitative analysis (analysis of nitrogen, sulphur, phosphorus and halogens). Quantitative analysis (estimation of carbon, hydrogen, nitrogen, halogens, sulphur, phosphorus and oxygen). Determination of molecular mass (Victor Mayer’s method, volumetric method). Calculation of empirical formula and molecular formula. Numerical problems in organic quantitative analysis, modern methods of structure elucidation.

15 . Organic Chemistry Based on Functional Group : (Halides and Hydroxy compounds) Nomenclature of compounds containing halogen atoms and hydroxyl groups : haloalkanes, haloarenes; alcohols and phenols. Correlation of physical properties and uses. Preparation, properties and uses of following. Polyhalogen compounds : Chloroform, Idoform Polyhydric compounds, Ethane 1, 2diol; Propane1,2,3 triol. Structure and reactivity – (a) Induction effect, (b) Mesomeric effect, (c) Electrophiles and Nucleophiles, (d) Types of organic reaction.

16 . Organic Chemistry Based on Functional Group II : (Ethers, aldehydes, ketones, carboxylic acids and their derivatives). Nomenclature of ethers, aldehydes, ketones, carboxylic acids and their derivatives. Sacylhalides, acid anhydrides, amides and esters). General methods of preparation, correlation of physical properties with their structures, chemical properties and uses. (Note : Specific compounds should not be stressed for the purpose of evaluation)

17 . Organic Chemistry Based on Functional GroupII : (Cyanides, isocyanides, nitrocompounds and amines) Nomenclature and classification of amines, cynadies, isocyanides, nitro compounds and their method of preparation; correlation of physical properties with structure, chemical reactions and uses.

18 . Chemistry of Nonmetals – (Hydrogen, Oxygen and Nitrogen) Hydrogen (position in periodic table, occurrence, isotopes, properties, reactions and uses) Oxygen (occurrence, preparation, properties and reactions, uses, simple oxides; ozone) Water and hydrogen peroxide (structure of water molecule and its aggregates, physical and chemical properties of water, hard and soft water, water softening, hydrogen peroxides, preparation, properties, structure and uses). Nitrogen(Preparation, properties, uses, compounds of Nitrogen – Ammonia, Oxides of Nitrogen, Nitric Acid – preparation, properties and uses).

19 . Chemistry of Nonmetals – II : (Boron, Carbon, Silicon, phosphorus, sulphur, halogens and the noble gases). Boron (occurrence, isolation, physical and chemical properties, borax and boric acid, uses of boron and its compounds). Carbon, inorganic compounds of carbon (oxides, halides, carbides), elemental carbon. Silicon (occurrence, preparation


and properties, oxides and oxyacids of phosphorus, chemical fertililzers). Sulphur (occurrence and extraction, properties and reactions, oxides: Sulphuric acid – preparation, properties and uses, sodium thiosulphate). Halogens (occurrence, preparation, properties, hydrogen halides, uses of halogens). Noble gases (discovery, occurrence and isolation, physical properties, chemistry of noble gases and their uses).

20 . Chemistry of lighter Metals : Sodium and Potassium (occurrence and extraction, properties and uses, important compounds – NaCl, Na2CO 3 , NaHCO 3 , NaOH, KCI, KOH). Magnesium and calcium (occurrence and extraction, properties and uses, important compounds MgCl 2 , MgSO 4 , CaO, Ca(OH) 2 , CaCO 3 , CaSO 4 , plaster of paris). Aluminium (occurrence, extraction, properties and uses, compounds – AlCl 3 , alums). Cement. Biological role of Sodium, Potassium, Magnesium and Calcium.

21 . Heavy Metals : Iron (Occurrence and extraction, compounds of iron, oxides, halides, sulphides, sulphate, alloy and steel). Copper, silver and gold (occurrence and extractions, properties and uses, compound – sulphides, halides and sulphates, photography). Zinc and Mercury (occurrence and extraction, properties and uses, compoundoxides, halides; sulphides and sulphates). Tin and Lead (occurrence and extraction, properties and uses, compounds – oxides, sulphides, halides).

22 . Chemistry of Representative Elements : Periodic properties – Trends in groups and periods (a) Oxidesnature (b) Halidesmelting points (c) Carbonates and sulphates – solubility. The chemistry of s and p block elements, electronic configuration, general characteristics properties and oxidation states of the following : Group 1 elements – Alkali metals Group 2 elements – Alkaline earth metals Group 13 elements – Boron family Group 14 elements – Carbon family Group 15 elements – Nitrogen family Group 16 elements – Oxygen family Group 17 elements – Halogen family Group 18 elements – Noble gases and Hydrogen

23 . Transition Metals including Lanthanides : Electronic configuration: General characteristic properties, oxidation states of transition metals. First row transition metals and general properties of their compoundsoxides, halides and sulphides. General properties of second and third row transition elements (Groupwise discussion). Preparation, properties and uses of Potassium dichromate, Potassium permaganate. Inner Transition Elements: General discussion with special reference to oxidation states and eamthanide contraction.

24 . Coordination Chemistry and Organo Metallics : Coordination compounds, Nomenclature : Isomerism in coordination compounds; Bonding in coordination compounds, Werner’s coordination theory.

25 . Nuclear Chemistry : Nature of radiation from radioactive substances. Nuclear reactions; Radioactive disintegration series; Artificial transmutation of elements; Nuclear fission and Nuclear fusion: Isotopes and their applications: Radio carbondating.

26 . Synthetic and Natural Polymers : Classification of Polymers, natural and synthetic polymers (with stress on their general methods of preparation) and important uses of the following : Teflon, PVC, Polystyrene, Nylon66, terylene Environmental pollution – pollutants – services – check and alternatives.

27 . Surface Chemistry : Surfaces : Adsorption Colloids – (Preparation and general properties), Emulsions, Micelles Catalysis : Homogeneous and heterogeneous, structure of catalyst.

28 . Bio Molecules and Biological Processes : The Cell Carbohydrates : Monosaccharides, Disaccharides, Polysaccharides Amino Acides and Peptides – Structure and classification. Proteins and Enzymes – Structure of Proteins, Role of enzymes. Nucleic Acids – DNA and RNA Biological functions of Nucleic acids – Protein synthesis and replication Lipids – Structure, membranes and their functions.

29 . Chemistry in Action : Dyes, Chemicals and medicines (antipyretic, analgesic, antibiotics & tranquilesers), Rocket propellants.<O:P (Structural formulae nonevaluative)

Key Topics in Biology for Class XI and XII

1 . General Biology : Biology and its branches; relationships with other sciences; scientific methods in Biology; historical breakthroughs; scope of Biology and career options; role of Biology in dispelling myths and misbeliefs; characters of living


organisms, (elementary idea of metabolism, transfer of energy at molecular level, open and closed system, homoeostasis, growth and reproduction, adaptation, survival, death).

2 . Systematics and Classification : Variety of living organisms; Systematics; need, history and types of classifications (ar tificial, natural, phylogenetic); biosystematics; binomial nomenclature; Two kingdom system, Five kingdom system, their merits and demerits, status of bacteria and virus; botanical gardens and herbaria; zoological parks and museums. Salient features of various plant groups; classification of angiosperms up to series level (Bentham and Hooker’s system). Salient features of nonchordates up to phylum level and chordates up to class level).

3 . Animal Kingdom : Classification of animal kingdom, characteristics of different phyla and their example. Morphology of Animals Salient features of earthworm, cockroach and rat; tissue systems, structure and function of tissues epithelial, connective, muscular and nervous.

4 . Plant Kingdom : Classification of plants groups, their characteristics and examples. 5 . Cell Biology : Cell as a basic unit of life — discovery of cell, cell theory, cell as a selfcontained unit; prokaryotic and

eukaryotic cell; unicellular and multicellular organisms; tools and techniques (compound microscope, electron microscope and cell fractionation); Ultrastructure of prokaryotic and eukaryotic cell cell wall, cell membrane unit membrane concept (fluid mosaic model); membrane transport; cellular movement (exocytosis, endocytosis); cell organelles and their functions nucleus, mitochondria, plastids, endoplasmic reticulum, Golgi complex, lysosomes, microtubules, centriole, vacuole, cy toskeleton, cilia and flagella, ribosomes. Molecules of cell; inorganic and organic materials — water, salt, mineral ions, carbohydrates, lipids, amino acids, proteins, nucleotides, nucleic acids (DNA and RNA); Enzymes (properties, chemical nature and mechanism of action); vitamins, hormones and steroids. Cell cycle : significance of cell division; amitosis, mitosis and meiosis; karyotype analysis.

6 . Genetics : Continuity of life heredity, variation; Mendel’s laws of inheritance; chromosomal basis of inheritance; other patterns of inheritance incomplete dominance, multiple allelism, quantitative inheritance. Chromosomes bacterial cell and eukaryotic cell; parallelism between genes and chromosomes; genome, linkage and crossing over; gene mapping; recombination; sex chromosomes; sex determination; sex linked inheritance; mutation and chromosomal aberrations; Human genetics methods of study, genetic disorders. DNA as a genetic material its structure and replication; structure of RNA and its role in protein synthesis; Gene expression transcription and translation in prokaryotes and eukaryotes; regulation of gene expression, induction and repression housekeeping genes; nuclear basis of differentiation and develop ment; oncogenes. Basics of Recombinant DNA technology; cloning; gene bank; DNA fingerprinting; genomics principles and applications, transgenic plants, animals and microbes.

7 . Human Biology : Nutrition and its types; nutrients food and vitamins; Intracellular and extracellular digestion; digestive system of invertebrate (cockroach); digestive system and process in humans (digestion, ingestion, absorption, assimilation, egestion); role of enzymes and hormones in digestion; malnutrition and undernutrition; disorders related to nutrition. Gaseous exchange in animals (earthworm, cockroach); respiration in humans respiratory organs, mechanism; breathing and its regulation : transport of gases through blood; common respiratory disorders prevention and cure. Circulation of body fluids open system in cockroach; closed system in humans, blood and its composition, structure and pumping action of human heart; pulmonary and systemic circulation; heart beat and pulse; rhythmicity of heartbeat, blood related disorders hypertension, atheroma and arteriosclerosis; ECG; pacemaker; lymphatic system, immunity and immune system. Nitrog enous waste elimination ammonetelism, ureotelism, uricotelism; excretory system of cockroach and humans; composition and formation of urine; role of kidney in osmoregulation, kidney failure; dialysis, kidney transplantation; role of ADH; role of liver in excretion. Locomotion and movements; human skeleton axial and appendicular including cranium and rib cage bones; Joints and their types; bone, cartilage and their disorders (arthritis, osteoporosis); mechanism of muscle contraction; red and white muscles in movements. Nervous coordination in cockroach and humans; human nervous system structure and functions of brain and spinal cord, transmission of nerve impulse; reflex action; sensory receptors; structure and function of sense organs eye, ear, nose and tongue. Human endocrine system; hormones and their functions; hormonal imbalance and diseases; role of hormones as messengers and regulators; hypothalamo hypophysial axis; feedback controls. Types of reproduction a general account (asexual and sexual); human male and female reproductive systems; Reproductive cycle in human female, gametogenesis; Fertilization physical and chemical events; development of zygote upto 3 germinal layers and their derivatives; extraembryonic membranes; general aspects of placenta. Cellular growth growth rate and growth curve; hormonal control of growth; mechanism and types of regeneration; ageing cellular and extracellular changes; theories of ageing.

8 . Angiosperm Botany : Morhpology root, stem and leaf, their structure and modification; Inflorescence, flower, fruit, seed and their types; Description of Poaceae, Liliaceae, Fabaceae, Solanaceae, Brassicaceae and Asteraceae. Internal structure of plants Tissues (meristematic and permanent); tissue systems; anatomy of root, stem and leaf of monocot and dicot; secondary growth. Cell as a physiological unit; water relations absorption and movement (diffusion, osmosis, plasmolysis,


permeability, water potential, imbibition); theories of water translocation root pressure, transpiration pull; transpiration significance, factors affecting rate of transpiration; mechanism of stomatal opening and closing (Potassium ion theory). Mineral nutrition functions of minerals, essential major elements and trace elements; deficiency symptoms of elements; translocation of solutes, nitrogen and nitrogen metabolism with emphasis on biological nitrogen fixation. * Photosynthesis significance, site of photosynthesis (functional aspect of chlorophyll structure); photochemical and biosynthetic phases; electron transport system; photophosphorylation (cyclic and noncyclic); C 3 and C 4 Pathway; photorespiration; factors affecting photosynthesis; mode of nutrition (autotrophic, heterotrophic saprophytic, parasitic and insectivorous plants), chemosynthesis. Mechanism of respiration glycolysis, Krebs cycle, pentose pathway, anaerobic respiration; respiratory quotient; compensation point; fermentation. Modes of reproduction in flowering plants vegetative propagation (natural and artificial), significance of vegetative propagation; micropropagation; sexual reproduction development of male and female gametophytes; pollination (types and factors); double fertilisation, incompatibility, embryo development, parthenogenesis and parthenocarpy. * Characteris tics of Plant growth; growth regulators (phytohormones) Auxins, gibberellins, cytokinins, ethylene, ABA; seed germination mechanism and factors affecting germination, role of growth regulators in seed dormancy; senescence; abscission; stress factors (salt and water) and growth; plant movement geotropism, phototropism, turgor growth movements (tropic, nastic and nutation), process of flowering photoperiodism, vernalisation.

9 . Ecology and Environment : Organisms and their environment; factors air, water, soil, biota, temperature and light; range o f tolerance; ecological adaptation. Levels of organisation population, species, community, ecosystem and biosphere; Eco logical interactions symbiosis, mutualism, commensalism, parasitism, predation and competition. Ecosystem structure and functions; productivity; energy flow; ecological efficiencies; decomposition and nutrient cycling; major blomes forests, grasslands and deserts. Ecological Succession types and mechanism. Natural resources types, use and misuse of natural resources. Environmental pollution kinds, sources and abatement of air, water, soil and noise pollution. Global environ mental changes; Greenhouse gases, global warming, sea level rise and ozone layer depletion. Biotic resources terrestrial and aquatic including marine resources; biodiversity benefits and assessment; threats, endangered species, extinctions; conserva tion of biodiversity (biosphere reserves and other protected areas); National and International efforts both governmental and nongovernmental; environmental ethics and legislation.

10 . Application of Biology : Population, environment and development; Population growth and factors (natality, mortality, immigration, emigration, age and sex ratio); impact of population growth; reproductive health; common problems of adolescence (Drugs, Alcohol and Tobacco); social and moral implications; mental and addictive disorders; Risks of indiscrimi nate use of drugs and antibiotics; population as a resource. * Food production, breeding, improved varieties, biofertilizers, plant tissue culture and its applications; Brief account of some common crop and animal diseases; biopesticides; genetically modified food; biowar, biopiracy; biopatent; biotechnology and sustainable agriculture. * Recent advances in vaccines; organ transplantation; immune disorders; modern techniques in disease diagnosis; Elementary knowledge of Haemoglobin estima tion and estimation of sugar and urea in blood, TLC, DLC, ESR, lipid profile, ELISA and VIDAL tests; AIDS, STD, cancer (types, causes, diagnosis, treatment); biotechnology in therapeutics hormones, interferon and immuno modulations. * Basic concepts of ECG, normal ECG, EEG, CT Scan, MRI and ultrasound.

11 . Evolution : Origin and evolution of Life OparinHaldane theory, Miller Experiment; theories of evolution; evidences of evolution; sources of variations (mutation, recombination, genetic drift, migration, natural selection); concept of species; speciation and isolation (geographical and reproductive); origin of species.

*******


What is Biotechnology? In the simplest terms, biotechnology is the use and manipulation of living things to make useful products to benefit human beings. More scientifically, it can be defined as any technique that uses living organisms, or substances from these organisms, to make or modify a product, to improve plants or animals, or to develop microorganisms. This technology contributes to such diverse areas as food production, waste disposal, mining, industry and medicine.

Some definitions of Biotechnology

• The application of biological organisms, system of manufacturing and service industries. • The integrated use of biochemistry. Microbiology and engineering sciences in order to achieve technological (industrial) application capabilities of microorganisms, cultured tissue cells and parts there of. • A technology using biological phenomena for copying and manufacturing various kinds of useful substance. • The application of scientific and engineering principles to the processing of materials by biological agents to provide goods and services. • The science of the production processes based on the action of microorganisms and their active components and of production processes involving the use of cells and tissues from higher organisms. Medical technology, agriculture and traditional crop breeding are not generally regarded as biotechnology. • Biotechnology is really no more than a name given to a set of techniques and processes. • Biotechnology is the use of living organisms and their components in agriculture, food and other industrial processes. • Biotechnology the deciphering and use of biological knowledge.

History of Biotechnology. Biotechnology has been around for a long time, dating back 3000 years with the fermentation process using yeast to make bread, beer and wine. As it has developed over the past centuries, biotechnology has passed through three clear generations or phases. The first involved the use of organisms to produce food, such as bread, wine, cheese and other fermented foods, and industrial products such as mining with microorganisms. This was followed by a second wave of innovation, using organisms and cells to produce new products such as antibiotics, enzymes and vitamins. This enabled the more effective use of the original, traditional techniques such as fermenting, which is now done on a large scale enabling the efficient industrial production by micro organisms of pure enzymes, additives and other valuable compounds for food. Penicillin production is one of the results of this generation that has benefited the entire world. The mainstay of this second generation was the careful selection and breeding of organisms for specific purposes.

BIOTECHNOLOGY

Time line from traditional to conventional to modern biotech


In the last 30 years, the third generation known as modern biotechnology or Genetic Modification (GM) has emerged. This is the further development of techniques previously used, but which are now more precise and effective, so enabling further benefit for human kind. GM techniques are applicable for plants, animals and microbes, but currently the greatest efforts are being undertaken in health care and crop production.

Subfields of biotechnology Red biotechnology is biotechnology applied to medical processes. Some examples are the designing of organisms to produce , and the engineering of genetic cures to cure diseases through genomic manipulation.

White biotechnology, also known as grey biotechnology, is biotechnology applied to industrial processes. An example is the designing of an organism to produce a useful chemical. White biotechnology tends to consume less in resources than traditional processes when used to produce industrial goods.

Green biotechnology is biotechnology applied to processes. An example is the designing of transgenic plants to grow under specific environmental conditions or in the presence (or absence) of certain agricultural chemicals. One hope is that green biotechnology might produce more environmentally friendly solutions than traditional industrial agriculture. An example of this is the engineering of a plant to express a, thereby eliminating the need for external application of pesticides. An example of this would be Bt corn. Whether or not green biotechnology products such as this are ultimately more environmentally friendly is a topic of considerable debate.

Bioinformatics is an interdisciplinary field which addresses biological problems using computational techniques. The field is also often referred to as computational biology. It plays a key role in various areas like functional genomics, structural genomics, and proteomics amongst others, and forms a key component in biotechnology and pharmaceutical sector. The term blue biotechnology has also been used to describe the marine and aquatic applications of biotechnology, but its use is relatively rare.

Applications of Modern Biotechnology include : • Insect, fungal and virus tolerance – by planting pest resistant crops less chemicals

(pesticides) are used, lowering production costs and reducing the impact on the environment. Examples include potato, maize, cotton and tomato.

• Stress tolerance – increasing the tolerance of crops to extreme stresses such as drought, salt and frost could enable resource poor farmers to produce food in areas where it is most needed.

• Herbicide tolerance – when such crops are planted, more environmentally friendly broadspectrum herbicides can be used. Examples include rice, cotton and beet;

• Enhanced food value and nutrition – such as changing oil profiles in oilseed crops, and developing vitamin enriched staple crops such as rice, wheat and corn. Research is also focusing on reducing allergens, and enriching crops with protein.

• Higher yields and greater crop stability – this increases crop production per unit of land.

• Control and minimise post harvest losses – this reduces the substantial losses after harvesting, and improves the shelf life of fruits and vegetables, such as tomato, contributing to a higher overall crop yield.


Monoclonal antibodies are new tools to detect and localize specific biological molecules. In principle, monoclonal antibodies can be made against any macromolecule and used to locate, purify or even potentially destroy a molecule as for example with anticancer drugs. Molecular biology is useful in many fields. DNA technology is utilized in solving crimes. It also allows searchers to produce banks of DNA, RNA and proteins, while mapping the human genome. Tracers are used to synthesize specific DNA or RNA probes, essential to localizing sequences involved in genetic disorders. With genetic engineering, new proteins are synthesized. They can be introduced into plants or animal genomes, producing a new type of disease resistant plants, capable of living in inhospitable environments (i.e. temperature and water extremes,...). When introduced into bacteria, these proteins have also produced new antibiotics and useful drugs. Techniques of cloning generate large quantities of pure human proteins, which are used to treat diseases like diabetes. In the future, a resource bank for rare human proteins or other molecules is a possibility. For instance, DNA sequences which are modified to correct a mutation, to increase the production of a specific protein or to produce a new type of protein can be stored . This technique will be probably play a key role in gene therapy.

Transfers of new genes into animal organisms

Culture of Plants from Single cells Diagnostics

Anticancer drugs

Monoclonal Antibodies

Cell culture

Crime Solving Tracers

Banks of DNA, RNA and Proteins Synthesis of

new proteins

Molecular Biology

Cloning Synthesis of specific DNA probes

Localization of genetic disorders

Mass production of human proteins

New types of plants and animals

Complete map of the human genome

New types of food

New antibiotics

resource bank for rare human chemicals

Gene Therapy

Genetic Engineering

DNA Technology


• Reduce the loss of top soil and biodiversity – by promoting low tillage production especially in marginal areas that are not ideal for agriculture;

• Development of improved livestock vaccines – for major diseases affecting productivity, diagnostic tools for disease detection and pedigree verification;

• Impact on smallscale farmers – with potentially large yield impacts and significant financial returns despite higher initial seed costs.

Human or pig The cloning of the human insulin gene (which diabetics lack) was made possible using a bacterium which enables vast quantities of human insulin to be produced at low cost. Prior to 1983, insulin was extracted from pigs and purified for diabetics to use, which was both more costly and less safe. Today, a large number of life saving drugs are produced in a similar way, such as human growth hormone and factor VIII which is a blood clotting protein lacking in haemophiliacs.

What Are The Benefits of Biotechnology ? Modern biotechnology can make an important contribution to the national priorities of a country in a number of areas: ♦ Enhanced Food Security

The promise of biotechnology in food production is its capacity to improve the quality and quantity of plants and animals quickly and effectively. ♦ Improved Health Care

In addition to improved health through enhancing the nutritional quality of foods, there are many other uses of modern biotechnology that can further enhance human health: • Inexpensive medicine production – Modern biotechnology is enabling the production of

higher quality drugs at a lower cost; • “Biopharming” – Crops are now being tested as possible delivery systems for

pharmaceuticals, such as banana which could one day contain various vaccines; • Human Genome Project – this research will one day enable genetic diseases to be

understood, diagnosed and perhaps cured; • Gene Therapy – medicines are being developed to target specific cells in the human

body; • HIV/AIDS – The production of vaccines for clinical trials is underway and if successful,

the companies undertaking the research could produce the vaccine in large amounts at low cost so they are affordable;

• Forensics and Diagnostics – also known as genetic fingerprinting, these techniques could provide invaluable evidence in bringing criminals to justice.


Environmental sustainability In addition to reducing the amount of toxic chemical pesticides that are released into the environment though built in resistance to pests, herbicide resistance means that more environmentally friendly broadspectrum herbicides can be used to eliminate competing weeds. More novel contributions GM can make towards sustainable development include: • Waste management: “Biomaterials” – biodegradable plastics are being developed using

a microorganism that degrades polyethylene plastics; • Bioremediation – the use of microorganisms such as bacteria to remove environmental

and often poisonous pollutants from soil and water. Waste cleaning organisms, mainly plants, could be grown at treatment plants and contaminated areas.

Industrial Development Processes Current GM research is opening up future possibilities which could significantly contribute to national economies, and promote new global collaborations, such as: • Engineering traditional food crops to become valuable industrial crops – e.g. canola is

being used to produce high value industrial oil; • Improved/additional characteristics for processing – such as potatoes that absorb less

oil, and fruits with a longer shelf life, such as tomato; • Transforming raw materials – useful enzymes are now mass produced at low cost and

high quality for various industries; • Biomining – this is the inexpensive extraction of precious metals from lowgrade ores

using microbes. Plants are also being developed to mine precious metals, for example Brassica, which concentrate gold from the soil in their leaves.

What are the problems and risks of Biotechnology? With all new technologies, there are risks and elements of unpredictability and modern biotechnology is no exception. There are a number of areas of concern associated with GM that must be taken into consideration by decision makers: Food safety Areas of concern include the potential detrimental effect of toxins, allergies, dangers of nutritional changes and antibiotic resistance, and unexpected effects. Foods safety issues have been extensively investigated and the consensus is that there is no greater risk of these effects from eating GM foods than from traditionally bred crop varieties. Before marketing, any GM food product has to be exhaustively tested by the developer and independently evaluated for safety by food scientists for all the above mentioned risks. These food safety assessments are decided nationally, but must be consistent with international standards. Environmental impact Impact assessments are carried out on all GMOs worldwide


prior to commercialisation and all GMOs are monitored after approval. Several longterm environmental impact studies are currently being conducted in many countries but to date, no negative impacts have been found. The specific areas of concern all relate to the potential impact of GM crops on other organisms in the same or near by environment, such as: • Nontarget organisms: built in resistance to pests may adversely affect other, non

target organisms; • Agrobiodiversity: the affect of modern biotechnology on local biodiversity found on

farms. GM crops are considered no more of a threat than traditionally bred varieties, which have contributed to genetic erosion of biodiversity. However, this risk remains, but is minimised when considered against the alternative of converting natural habitats to agriculture;

• Invasive species: GM, whether through traditional breeding, natural changes or modern biotechnology can potentially change an organism to be an invasive species, which is something that spreads widely in its nonnative environment. Either the GM species could become invasive (i.e. a weed) or it could breed with a wild

or weedy relative and so produce invasive offspring. Invasiveness of all GM plants, animals and microbes is assessed before decisions are made; • Gene Flow: The concern is that the inserted gene(s) could be passed into other species.

Genes do flow or move between species, and the impact of such movement is always assessed before decisions are made.

Socioeconomic concerns These concerns are not specific to GM, but are the same for any new technology, including: • Access to affordable seed and sustainable development for poor communities – there

is a fear of multinational companies controlling food production in developing countries; • Globalisation, trade issues, income inequality and Intellectual Property Rights (IPRs)

– any technology should be available for development and used to benefit the local markets and farmers. A further concern is that increased yields of commodity crops will cause the price to drop, which could be detrimental to the farmer, but good news for the consumer;

• Dietary preferences – the use of animal genes in plants has implications for vegetarians and some religious groups;

• Ethics – the choice of the consumer to eat GM or not and whether it is morally, personally acceptable to transfer genes from species to species in this manner. The ethics of using GM crops should be compared to the ethics of not using the technology;

• Problems associated with replanting seed – privately developed seed must be bought each year. There is also the risk that farmers who have not paid for GM seed will have their crops affected through pollen movement;

• Development of resistance – built in resistance could favour the development of resistance within the pest population, as is the case with all pest control systems;


• Impact on organic farming – GM genes could flow to neighbouring organic farmers, decertifying organic products and possibly devaluing the harvest. Mechanisms (isolation barriers, established distances, alternate planting dates etc) can all be implemented to maintain GM free harvests;

• Labelling – allowing the consumer to choose (and possibly pay more) GM or GM free products. This is a complex issue as it is difficult to trace all products and derivatives. However, all GM foods are safety approved and labelling may incorrectly imply there is a safety risk. This has implications in developing countries where literacy levels are low and the cost of food critical. Existing international labelling standards already cover the safety needs of food labelling, such as presence of allergens and changes in nutrition or intended use.

Across 1 . Type of bond joining

complementary base pairs. 5 . Two nitrogen bases held together

are known as. 7 . The study of the human body is

known as. 10 . A protein that speeds up a chemical

reaction. 12 . Central region of the cell where

genetic material is found. 14 . The order of base pairs that makes

us unique. 15 . If one allele is expressed over the

other it is said to be _____. 16 . Building blocks of life; made of

multiple amino acids.

Down 2 . A subunit of DNA that contains a

base, sugar, and phosphate. 3 . Substances in the blood that help

the body protect itself. 4 . A change, wanted or unwanted, in

the DNA sequence. 6 . Proteins on the surface of blood

cells that help ID blood type. 8 . All the genetic material in the

chromosomes of an organism. 9 . If an allele is not expressed it is said

to be _____. 11 . Unit of inheritance located on a

chromosome. 13 . The selfreplicating genetic

structure of cells.

Search for Answer! Crossword puzzle


What is cloning? If you were told that there was a clone of you sitting in the next room, what would you expect the clone to look and act like? Probably, exactly the same as you. But, despite all the movies and TV programmes that have explored the possibility of exact clones, it is highly unlikely that a clone of you would look exactly the same and would certainly not act exactly the same. A clone is not completely genetically identical, as there are small differences in the genetic makeup just as there are with identical twins. Despite the fact that identical twins come from the same egg, after a while one begins to notice the differences between them in order to tell them apart. It has been discovered – by doing a number of studies on identical twins brought up in the same environment – that genes mysteriously react differently to the same environment. While cloning a whole human is certainly the ultimate challenge for genetic engineers, cloning is not limited to this goal. Cloning can be, and is, done on a much smaller scale and could involve no more than just the cloning of a single cell. Therefore, cloning can be divided into two types: 1. reproductive cloning (which is the cloning of a whole organism); and 2. therapeutic cloning (which is the cloning of cells or even organs or other tissue for

transplant purposes). Due to the fact that genetic differences are likely to exist between a clone and its donor, this uncertainty has led to many countries banning the reproductive cloning of humans. How are clones made? Reproductive cloning: In order to make a clone of someone, one needs a living cell and a human egg (ovum). The nucleus of the egg, which contains the DNA, is removed and replaced with the nucleus from the cell of the person/animal to be cloned. A short electrical pulse then stimulates the egg to start dividing and the embryo is then implanted into the womb where it develops into a duplicate of the person that donated the cell nucleus. Clones created in this way are not 100% genetically identical, as there is some DNA from the original egg cell that is found outside the nucleus (mitochondrial DNA).

ALL ABOUT CLONING


Lamb born is clone of sheep 1

Nucleus removed

Nucleus from sheep 1 fuses with empty egg from sheep 2 and

starts to divide to form an embryo

The cloned embryo is implanted into the uterus of sheep 3

Sheep 1 Sheep 2

Sheep 3

Adult udder cell

Mature ovum

Mild electric shock

Remove nucleus empty ovum

Adult Cell or reproductive cloning


Early embryo (cluster of indentical cells)

No Nucleus ovum

Cells separated

Each cell develops into an identical embryo

Each embryo is implanted into a different surrogate mother

Identical cloned offspring born

Embryo cloning

Therapeutic cloning and stem cells: In therapeutic cloning an embryo is created in the same way as reproductive cloning, but it is not implanted into the womb of a woman. Instead, stem cells are extracted after the embryo starts dividing in the first 14 days after fertilization, which kills the embryo. Stem cells are special cells with the ability to reproduce and become one of 300 types of cells, eg, skin, liver cell, hair or blood cells. These cells are then used to grow the specific type of tissue or organ that is needed and has the advantage of being genetically identical to the patient who donated it, eliminating the problem of organ or tissue rejection. Currently, if someone has an organ transplant, there is quite a high possibility that their body will reject the foreign organ and so they not necessary have to suppress the immune system to lessen the chances of this happening. Stem cells could potentially be used to repair damaged or defective tissues around the body, such as the cells in the pancreas that stop producing insulin in diabetics.


Person who needs new organ or tissue

Adult cell from patient

Mild electric shock

Human ovum

Remove nucleus empty ovum

New preembryo cell containing patient DNA

Embryonic development begins

Stem cells removed from embryo and cultured to grow into required organ or tissue

Insulin producing cells

Spinal cord Kidney Heart

Organ or tissue transplanted into patient with no rejection problems

Potential uses of cloning Although currently the risks of cloning outweigh the possible benefits, there are many different potential uses of human cloning technology: • Replacing organs and other tissues – such as new skin for burn victims, brains cells

for those with brain damage, spinal cord cells for the paralysed and complete new organs (hearts, liver, kidney and lungs). Pigs are also being genetically modified to make their organs more compatible with humans by removing the gene that causes rejection. People could have their appearance changed (cosmetic surgery) using their

nucleus extracted


own cloned tissue and accident victims and amputees could also benefit from this tissue regeneration.

• Infertility – human cloning provides couples and individuals who are unable to have children with another potential option.

• Replacement of a lost child – parents who have lost a child through an accident or an illness could clone an identical “replacement” child.

• Creating “donor” people – cloned people could be created to provide a source of transplant material.

• Gene therapy – cloning technology could be used to prevent, treat and cure genetic disorders by changing the expression of a person’s genes. This technology may also provide the cure for cancer by revealing how cells are switched on and off. Gene therapy could be used to treat somatic (body) cells where the change is not passed on to children, or germ (egg and sperm) cells where the changes are passed on.

• Saving endangered species – by boosting their numbers through creating clones. However, since clones are almost genetically identical, the genetic diversity of the species would not be increased.

• Reversal of the ageing process – once more is understood about the role that our genes play in the ageing process. However, some of the above uses carry with them some serious ethical implications.

Problems with cloning techniques Dolly the sheep was created in 1996 using the cloning methods outlined above. Although Dolly was born looking normal, she has suffered from several problems associated with the cloning technique, including premature arthritis, which is thought to be a sideeffect of the cloning. Other problems with the current cloning techniques, include: 1. Low success rate: Dolly the sheep was successfully cloned, It took 276 unsuccessful

attempts before it worked. Similar work on mice and other mammals has also produced the same statistics. To date, the success rate (on animals) is 34%.

2. Tumours: Embryonic stem cells are unstable and difficult to control. They have a tendency to uncontrollably divide leading to tumours/cancer.

3. Genetic defects:Although the original DNA from an embryo is removed and replaced with the nucleus from the person to be cloned, some DNA from the original embryo remains in the form of mitochondrial DNA. This can lead to genetic defects that are not fully understood and which are only seen in later life.


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4. Overgrowth syndrome: Clones of animals are larger than average at birth, which can be risky for the mother.

5. Premature ageing: The age of a clone is calculated by taking its birth age and then adding the age of the original from which it was cloned. Although Dolly was born in 1996, she originates from the udder of a six year old ewe and so her total genetic age is almost 13.

6. Massive quantities of human eggs required: If applied to humans, the current method of cloning would use a vast number of human eggs. To provide these eggs, women would have to become “egg factories”, and harvesting them is both painful and dangerous. If adult stem cells were used, then human eggs would not be required as cells could be obtained from the patient without harming them.

7. Reduction in adaptability: Since, by nature, a clone is a copy of another person, there would be no unique genetic combinations introduced into the human gene pool if human cloning was undertaken on a large scale. Therefore, if a contagious disease struck for which there was no cure, all the clones would be wiped out.

8. Insertion of the gene: In gene therapy where a healthy gene can be used to replace a defective gene, viruses are usually used to insert the gene into the person’s cells. The virus injects the healthy DNA into the cells and the genetic defect is corrected. However, this is not always successful as the virus cannot always be controlled and has triggered leukaemia in a recent clinical trial in France.

9. Lack of knowledge: Although the Human Genome Project has mapped out where the different genes are, a lot more information is needed on their functions. In some cases, a single gene may have more than one function, and in others several genes can cause a genetic disease.

A Big Question What do you think cloning should be banned or encouraged?


Our cells are kept extremely busy linking together amino acids—the building blocks of proteins—in the right order to produce varying quantities of the 40,000 different proteins we need every day. The order of these amino acids is determined by the genes. According to the genetic code, which was deciphered in the 1960s, each triplet of bases in the genes’ instructions either calls for a particular amino acid or gives a signal to start or stop making a protein. An error in just one base can bring the wrong amino acid, altering the protein. And should one or two bases be missing, each succeeding triplet will be read in the wrong combination; such “readingframe shifts” generally prevent cells from making the protein at all. Actually the DNA’s instructions are not transmitted directly; a copy made of ribonucleic acid (RNA) acts as an intermediary. The original DNA remains safely in the nucleus, somewhat like the printing block in a printing press, while the RNA copy is produced by transcribing just one strand of DNA, which carries the genetic instructions. Reading the DNA of humans and other mammals is complicated by the astonishing fact— discovered over a decade ago—that the instructions for making a protein are split into separate segments of DNA. These instructions must be spliced together before they can be carried out by a cell. Only about 5 percent of the DNA in mammalian genes actually contains the recipe for making a protein. The remaining 95 percent consists of intervening sequences, or “introns,” whose function is unknown. Splicing together the “exons”—the proteincoding sequences—is a very delicate, precise operation that involves snipping out the introns to end up with a much shorter strand of potent RNA. At the exon–intron boundaries are splicing signals, which researchers can now identify. Several genetic diseases have been traced to disrupted splicing.

THE GENETIC RECIPE FOR MAKING PROTEINS


As scientists learn to read the instructions in our genes, they are discovering that much of our DNA is riddled with errors. Fortunately, most of these errors are harmless. Considering the difficulties involved—the 6 feet of DNA in a human cell consists of 6 billion subunits, or base pairs, coiled and tightly packed into 23 pairs of chromosomes, all of which must be duplicated every time a cell divides—this is something of a miracle.

We each inherit hundreds of genetic mutations from our parents, as they did from their forebears. In addition, the DNA in our own cells undergoes an estimated 30 new mutations during our lifetime, either through mistakes during DNA copying or cell division or, more often, because of damage from the environment.

Bits of our DNA may be deleted, inserted, broken, or substituted. Most mutations affect only the parts of DNA that do not contain instructions for making a gene, so we need not worry about them. Problems arise only when an error in DNA alters a message that tells certain cells to manufacture a certain protein. Such messages are spelled out in varying sequences of the four chemical bases that make up DNA: adenine (A), thymine (T), guanine (G), and cytosine (C).

To stay alive and functioning, the human body requires a daily crop of billions of fresh protein molecules—about 40,000 different kinds of proteins that must be supplied in the right quantities, at the right times, and in the right places. We need hemoglobin to carry oxygen through the bloodstream, antibodies to fight foreign substances, hormones to deal with stress, neurotransmitters to evoke movements, emotions, and thought, and many other proteins to give structure to organs or speed up chemical reactions.

Much of the recent progress in reading DNA has come from analyses of genetic errors.

30 NEW MUTATIONS PER LIFETIME


Gene tests involve the examination of the DNA molecule. DNA samples can be obtained from any tissue, including blood. In most cases, a gene test involves scanning a patient’s DNA for mutated sequences. In some cases researchers use short pieces of DNA called probes, whose sequences are the same as the mutated sequences for which they are searching. The probes look for their twin among the three billion base pairs of an individual’s genome. If the mutated sequence is present in the patient’s DNA, the probe will stick to it, thereby making it possible for the researchers to confirm that the mutation exists. Another type of DNA testing involves comparing the sequence of DNA bases in a patient’s gene, to a normal, or functional, version of the gene in order to diagnose the presence or absence of a disease. Unfortunately, DNA testing is usually very expensive depending on the size of the mutated sequence that is being tested. The cost of a DNA test can range from hundreds to tens of thousands of rupees. Genetic tests are used for several reasons, including : • Carrier screening which tests unaffected individuals who carry one copy of a gene

for a disease that needs two copies for the disease to become active. In other words, if two parents carry the diseased gene, then their children will inherit the disease.

• Prenatal diagnostic testing which tests the amniotic fluid from the uterus of an expectant mother, to see if the child has got a disease. This procedure is known as amniocentesis and is usually carried out in pregnant women over the age of 35.

• Presymptomatic testing for predicting adultonset disorders such as Huntingtons disease. Huntingtons disease is a single gene disorder of the central nervou system which usually develops in adult men and women. It is caused by a faulty gene in chromosome four.

• Unfortunately, it is not yet fully understood how the faulty gene damages the nerve cells in areas of the brain, leading to gradual physical, mental and emotional deterioration. Many people choose not to be tested as there is, as yet, no cure for the disease.

• Presymptomatic testing for estimating the risk of developing adultonset cancers and Alzheimers disease.

• Tests to confirm a disease in someone who is already showing symptoms of that disease.

• Forensic or identity testing : if a man wants proof that a child is (or isn’t) his offspring, he can ask for DNA identity testing to be done. DNA identity testing is also done when someone has died and their remains make it impossible to identify them. These identity tests can also be used to link a criminal to a crime scene if no other evidence is available.

WHAT IS GENE TESTING ?


Gene therapy is designed to introduce genetic material into cells to compensate for abnormal genes or to make a beneficial protein. If a mutated gene causes a necessary protein to be faulty or missing, gene therapy may be able to introduce a normal copy of the gene to restore the function of the protein. Gene therapy researchers have employed two major strategies for delivering therapeutic transgenes into human recipients. The first is to “directly” infuse the gene into a person. Viruses that have been altered to prevent them from causing disease are often used as the vehicle for delivering the gene into certain human cell types, in much the same way as ordinary viruses infect cells. This delivery method is fairly imprecise and limited to the specific types of human cells that the viral vehicle can infect. For example, some viruses commonly used as genedelivery vehicles can only infect cells that are actively dividing. This limits their usefulness in treating diseases of the heart or brain, because these organs are largely composed of nondividing cells. Nonviral vehicles for directly delivering genes into cells are also being explored, including the use of plain DNA and DNA wrapped in a coat of fatty molecules known as liposomes.

WHAT IS GENE THERAPY?

Strategies for Delivering Therapeutic Transgenes into Patients

Direct Delivery Cellbased delivery

Terapeutic transgene

The therapeutic transgene is packaged into a delivery vehicle

such as a virus.

The therapeutic transgene is

packaged into a delivery vehicle such as a virus.

Therapeutic transgene

...and injected into the pattent.

Target organ (e.g., liver) The therapeutic

transgene is introduced into a

delivery cell such as a stem cell that is often

derlved from the pattent.

The genetically modified cells (e.g., stem cells) are multiplied in the

laboratory. ...and readministered to

the patient.


The second strategy involves the use of living cells to deliver therapeutic transgenes into the body. In this method, the delivery cells—often a type of stem cell, a lymphocyte, or a fibroblast—are removed from the body, and the therapeutic transgene is introduced into them via the same vehicles used in the previously described directgenetransfer method. While still in the laboratory, the genetically modified cells are tested and then allowed to grow and multiply and, finally, are infused back into the patient.

Researchers must overcome many technical challenges before gene therapy will be a practical approach to treating disease. For example, scientists must find better ways to deliver genes and target them to particular cells. They must also ensure that new genes are precisely controlled by the body.

A new gene is injected into an adenovirus vector, which is used to introduce the modified DNA into a human cell. If the treatment is successful, the new gene will make a functional protein.

Viral DNA

New Gene

Viral DNA

Vector binds to cell mermbrane

Vector is packaged in vesicle

Vesicle breaks down releasing vector

Cell makes protein using new gene

Vector injects new gene into nucleus

Vector (adenovirus)


What if doctors had tiny tools that could search out and destroy the very first cancer cells of a tumor developing in the body? What if a cell’s broken part could be removed and replaced with a functioning miniature biological machine? Or what if moleculesized pumps could be implanted in sick people to deliver lifesaving medicines precisely where they are needed? These scenarios may sound unbelievable, but they are the ultimate goals of nanomedicine, a cuttingedge area of biomedical research that seeks to use nanotechnology tools to improve human health. Medical nanites could patrol the body, armed with a complete knowledge of a person’s DNA, and dispatch any foreign invaders. Such cell sentinels would form an artificial immune system and immunity to not only the common cold, but also AIDS and any future viral or bacterial mutations. No pain, no bruising and results over night. People shall be able to sculpt their own bodies. What is a nanometer? A lot of things are small in today’s hightech world of biomedical tools and therapies. But when it comes to nanomedicine, researchers are talking very, very small. A nanometer is one billionth of a meter, too small even to be seen with a conventional lab microscope. What is nanotechnology? Nanotechnology is the broad scientific field that encompasses nanomedicine. It involves the creation and use of materials and devices at the level of molecules and atoms, which are the parts of matter that combine to make molecules. Nonmedical applicat ions of nanotechnology now under development include tiny semiconductor chips made out of strings of single molecules and miniature computers made out of DNA, the material of our genes. Fields of Application Some possible applications using nanorobots are as follows :

1. To cure skin diseases, a cream containing nanorobots may be used. It could remove the right amount of dead skin, remove excess oils, add missing oils, apply the right

SMALL MACHINE TO TACKLE BIG DEALS

Nanorobots Nanorobots are nanodevices that will be used for the purpose of maintaining and protecting the human body against pathogens. They will have a diameter of about 0.5 to 3 microns and will be constructed out of parts with dimensions in the range of 1 to 100 nanometers. The main element used will be carbon in the form of diamond / fullerene nanocomposites because of the strength and chemical inertness of these forms. Many other light elements such as oxygen and nitrogen can be used for special purposes. To avoid being attacked by the host’s immune system, the best choice for the exterior coating is a passive diamond coating. The smoother and more flawless the coating, the less the reaction from the body’s immune system. Such devices have been designed in recent years but no working model has been built so far. When the task of the nanorobots is completed, they can be retrieved by allowing them to exfuse themselves via the usual human excretory channels. They can also be removed by active scavenger systems. This feature is designdependent.


The characteristics of all living organisms, including humans, are essentially determined by information contained within the DNA inherited from their parents. DNA directs how cells develop and controls the way characteristics, like eye color, are passed on from one generation to the next. The molecular structure of DNA can be imagined as a zipper. Each tooth of the zipper is represented by one of four letters (A, C, G, or T). The information contained in DNA is determined by the sequence of letters along the zipper. For example, the sequence ACGCT represents different information than AGTCC just as the word “POST” has a different meaning than “STOP” or “POTS,” though they use the same letters. Living organisms that have different characteristics also have different DNA sequences. DNA fingerprinting is a very quick way to analyze and compare the DNA sequences of any living organisms. DNA Fingerprinting DNA fingerprinting is a laboratory procedure that requires following steps : Southern Blot The Southern Blot is one way to analyze the genetic patterns which appear in a person’s DNA. Performing a Southern Blot involves: 1. Isolating the DNA in question from the rest of the cellular material in the nucleus. This

can be done either chemically, by using a detergent to wash the extra material from the DNA,or mechanically, by applying a large amount of pressure in order to “squeeze out” the DNA.

2. Cutting the DNA into several pieces of different sizes. This is done using one or more restriction enzymes.

3. Sorting the DNA pieces by size. The process by which the size separation, “size fractionation,” is done is called gel electrophoresis. The DNA is poured into a gel, such as agarose, and an electrical charge is applied to the gel, with the positive charge at the bottom and the negative charge at the top. Because DNA has a slightly negative charge, the pieces of DNA will be attracted towards the bottom of the gel; the smaller pieces, however, will be able to move more quickly and thus further towards the bottom than the larger pieces. The differentsized pieces of DNA will therefore be separated by size, with the smaller pieces towards the bottom and the larger pieces towards the top.

DNA FINGERPRINTING


Because VNTR patterns are inherited genetically, a given person’s VNTR pattern is more or less unique. The more VNTR probes used to analyze a person’s VNTR pattern, the more distinctive and individualized that pattern, or DNA fingerprint, will be.

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Applications of DNA Fingerprinting Mapping Paternity and Maternity Because a person inherits his or her VNTRs from his or her parents, VNTR patterns can be used to establish paternity and maternity. The patterns are so specific that a parental VNTR pattern can be reconstructed even if only the children’s VNTR patterns are known (the more children produced, the more reliable the reconstruction). Parentchild VNTR pattern analysis has been used to solve standard fatheridentification cases as well as more complicated cases of confirming legal nationality and, in instances of adoption, biological parenthood. Criminal Identification and Forensics DNA isolated from blood, hair, skin cells, or other genetic evidence left at the scene of a crime can be compared, through VNTR patterns, with the DNA of a criminal suspect to determine guilt or innocence. VNTR patterns are also useful in establishing the identity of a homicide victim, either from DNA found as evidence or from the body itself. Personal Identification The notion of using DNA fingerprints as a sort of genetic bar code to identify individuals has been discussed, but this is not likely to happen anytime in the fore seeable future. The


technology required to isolate, keep on file, and then analyze millions of very specified VNTR patterns is both expensive and impractical. Social security numbers, picture ID, and other more mundane methods are much more likely to remain the prevalent ways to establish personal identification. Breeding Consider the simple example of three genes in a cross between two individuals: Aa Bb Cc X Aa Bb Cc in which the goal of the breeder is to produce individuals that have the genotype AA BB CC. (A, B, and C are dominant genes and a, b, and c are recessive genes.) Classical genetics gives the probability of offspring with the genes AA BB CC as 1/64. A breeder traditionally uses the appearance (phenotype) of an animal or plant to judge the genotype (DNA) that has been inherited. However, there are problems when the phenotype is used to select individuals for breeding. A, B, or C may be genes that are difficult to observe or measure. Or homozygous individuals (AA) may be impossible to distinguish from heterozygous (Aa) individuals, because the dominant A gene would cause them to look alike. DNA fingerprinting can make the selection process more precise. If DNA markers are known for the genes A, B, or C, then DNA fingerprinting can accurately measure the genotype to ensure that the breeder correctly identifies homozygous (AA, BB, or CC) and heterozygous (Aa, Bb, or Cc) individuals. DNA fingerprinting can also speed the selection process and reduce the costs considerably. DNA tests can be done on embryonic tissue. Even at this early stage, the DNA test accurately predicts the gene an individual possesses. Transgenics Transgenics is the science of intentionally introducing a foreign gene or genetic construct into the genome of a target animal. The organism carrying the introduced foreign gene is called transgenic plant/animals. Before transgenic plants or animals can be developed, the DNA code necessary for the desired trait must be known and identified. Gene mapping, described earlier, is a method to identify the genes responsible for specific traits. Legal Protection Because of the uniqueness of DNA fingerprint data, the technique can be used to legally protect new varieties of plants or animals, whether they were developed by genetic engineering, tissue culture, or traditional methods. Using DNA fingerprints to identify and protect commercial varieties of crops or livestock is a relatively new application of DNA fingerprint technology.


1. Which of the following primers would allow copying of the single stranded DNA sequence? 5' ATGCCTAGGTC? A. 5' ATGCC B. 5' TACGG C. 5' CTGGA D. 5' GACCT E. 5' GGCAT

2. Which of the following tools of recombinant DNA technology is INCORRECTLY paired with its use? A. restriction endonuclease production of DNA fragments for gene cloning. B. DNA ligase enzyme that cuts DNA, creating sticky ends. C. DNA polymerase copies DNA sequences in the polymerase chain reaction. D. reverse transcriptase production of cDNA from mRNA. E. electrophoresis RLFP analysis.

3. The “Southern” technique involves: A. the detection of RNA fragments on membranes by specific radioactive antibodies. B. the detection of DNA fragments on membranes by a radioactive DNA probe. C. the detection of proteins on membranes using a radioactive DNA probe. D. the detection of proteins on membranes using specific radioactive antibodies. E. the detection of DNA fragments on membranes by specific radioactive antibodies.

4. DNA from a eukaryotic organism is digested with a restriction endonuclease and the resulting fragments cloned into a plasmid vector. Bacteria transformed by these plasmids collectively contain all of the genes of the organism. This culture of bacteria is referred to as a: A. restriction map B. RFLP profile C. F’ factor D. library E. lysogenic phage

5. Which of the following is not a part of the normal process of cloning recombinant DNA in bacteria?

A. restriction endonuclease digestion of cellular and plasmid DNAs. B. production of recombinant DNA using DNA ligase and a mixture of digested cellular and

plasmid DNAs. C. separation of recombinant DNAs by electrophoresis using the Southern technique to determine

where the desired recombinant migrates. D. transformation of bacteria by the recombinant DNA plasmids and selection using ampicillin . E. probing blots of bacteria clones with radioactive DNA complementary to the desired gene.

Activity :

DNA to be cloned and plasmid DNA cut with same restriction endonuclease

DNA fragments and open plasmid spliced with DNA ligase


6. Restriction endonuclease generated DNA fragments separated by gel electrophoresis and blot transfered onto a membrane filter are probed with a radioactive DNA fragment. This procedure is called : A. Gene cloning B. The Southern technique C. The polymerase chain reaction D. Recombinant DNA E. Gene mapping

ANSWERAND EXPLANATION TOACTIVITIES

1. The process of DNA replication uses RNA primers. To make a copy of DNA from a known part of the chromosome, for example by PCR, short primers of DNA are added to DNA in a test tube and the appropriate enzymes are included to make a copy of the DNA. The primers must be complementary to the DNA and obey the polarity rule. For the sequence: 5' ATGCCTAGGTC the primer would have to be 5’GACCT. Extending the 3' T would copy the single stranded DNA sequence. Ans. (D) : 5' GACCT The 3' end of the template strand starts the 5' of the newly synthesized DNA.

2. Creating Recombinant DNA A plasmid vector is digested with EcoRI at a single site to produce two sticky ends. A sample of human DNA is also digested with EcoRI to produce pieces with the same sticky ends. Human DNA or cDNA copied from mRNA using reverse transcriptase from retroviruses. The two samples are mixed and allowed to hybridize, some molecules will form with pieces of human DNA inserted into the plasmid vector at the EcoRI site. DNA ligase is used to covalently link the fragments. Ans (B) :DNA ligase enzyme that cuts DNA, creating sticky ends. DNA ligase joins adjacent nucleotides in a covalent linkage. Restriction endonucleases cut DNA at specific sites creating sticky ends.

3. Separating DNA by gel electrophoresis DNA is taken from individualsAandB It is digested with restriction endonuclease Fragments are applied onto an Agarose gel for electrophoresis. DNA has a negative charge, and in an electric field migrates towards a positive electrode. The rate of migration through a gel is proporational to the size of the fragment.

Joining of cohesive ends

Foreign DNA

Vector Restriction Enzyme Fragments

Restriction Enzyme

Recombinant Plasmid

Cut Plasmid


Transfering DNA fragments to nitrocellulose sheets DNA fragments are transfered to nitrocellulose sheets where they bind. DNA fragments are denatured and separated by gel electrophoresis. Fragments are blotted onto a sheet of nitrocellulose and fixed by heating. Blot is reacted with a radioactive probe of RNA or DNA which binds to complementary DNA. Autoradiography is used to detect radioactive fragments Fixing the fragments of DNA The denatured fragments of DNA are fixed by baking. A radioactive probe is added. It can hybridize with a gene sequence in the DNA. The sheet is rinsed and placed next to Xray film for autoradiography. Ans (B) : the detection of DNA fragments on membranes by a radioactive DNA probe. The Southern technique detects fragments of DNA using a radioactive DNA probe.

4. Gene library When the genomic DNA is digested by a restriction endonuclease, and all fragments cloned at random into a plasmid vector, then the majority of genetic information will be included in the mixture of bacteria. Cultures of the bacteria, with each containing only a fraction of the genome, collectively contain all the genes and are called a library. Ans (D) : library A library is a culture of bacteria where each cell has one or a few DNA sequences from another organism, but the whole culture contains the majority of the DNA fragments from an organism.

5. Creating recombinant DNA A plasmid vector is digested with EcoRI at a single site to produce two sticky ends. A sample of human DNA is also digested with EcoRI to produce pieces with the same sticky ends. Human DNA or cDNA copied from mRNA using reverse transcriptase from retroviruses. The two samples are mixed and allowed to hybridize, some molecules will form with pieces of human DNA inserted into the plasmid vector at the EcoRI site. DNA ligase is used to covalently link the fragments.

NO 2 , Cellulose Paper towels

Plasmids containing different inserts

bacteria transformed with mixture or plasmids

culture of host bacteria

each colony is a volume in the gene library


Ans. (C) : separation of recombinant DNAs by electrophoresis using the Southern technique to determine where the desired recombinant migrates. The Southern technique is used to detect where fragments of DNA migrate on a gel during electrophoresis.

6. The Southern Technique Transfering DNA fragments to nitrocellulose sheets DNA fragments are transfered to nitrocellulose sheets where they bind. DNA fragments are denatured and separated by gel electrophoresis Fragments are blotted onto a sheet of nitrocellulose and fixed by heating Blot is reacted with a radioactive probe of RNA or DNA which binds to complementary DNA Autoradiography is used to detect radioactive fragments Fixing the fragments of DNA The denatures fragments of DNA are fixed by baking. A radioactive probe is added. It can hybridize with a gene sequence in the DNA. The sheet is rinsed and placed next to Xray film for autoradiography. Ans. (B) : The Southern technique The Southern technique detects the location of DNA fragments on gel electrophoresis.


Biotechnology and genetic engineering have long promised to revolutionize the biological sciences. Recent research may bring this promise to fruition. The research focuses on using plants to produce human blood components.

In the experiments, tobacco plants were modified to produce human blood components. The necessary human genes were transplanted into the tobacco plants. Among the substances and factors produced were thrombin, factor XIII, and coagulation factor VIII. Traditionally, these blood factors are made from blood plasma or through the cultivation of certain types of mammal cells. These procedures can be more risky when compared to the production using plants. Producing blood components using plants prevents the spread of diseases that may go undetected in human plasma.

The cost savings can also be enormous. The researchers estimate that the production through the use of plants could be from eight to ten times cheaper than current production methods.

Unlike production from humans, the production from the tobacco plant provides a stable source over time. The purified amounts of the substances are also much higher.

BLOOD FROM A PLANT


The science of phytoremediation arose from the study of heavy metal tolerance in plants in the late 1980s. The discovery of hyperaccumulator plants, which contain levels of heavy metals that would be highly toxic to other plants, prompted the idea of using certain plant species to extract metals from the soil and, in the process, clean up soil for other less tolerant plants. Scientists also found that certain plants could degrade organic contaminants by absorbing them from the soil and metabolizing them into less harmful chemicals. In addition to plants, microorganisms that live in the rhizosphere (the actively growing root zone of the soil) play a major role in degrading organic chemicals, often using these chemicals as a carbon source in their metabolism. In many cases, even the physical presence of a plant can improve the condition of the soil, giving it structure and stability and altering hydrology by enhancing water retention and preventing erosion. There is no doubt that plants and the microbes associated with them can profoundly alter an ecosystem. Different types of phytoremediation have different potential results, such as accumulation of heavy metals in specific plant organs, volatilization from leaf surfaces, alteration of the

WHAT IS PHYTOREMEDIATION?


form or availability of an organic chemical in the soil or within the plant, or actively excluding chemicals from plant tissues and keeping them out of the food chain. The result depends on sitespecific research and this approach is not generally appropriate for grossly contaminated soils that are an immediate ecological health risk.

Phytoremediation is the use of living plants for insitu (in place) remediation and cleanup of contaminated soil, sludge, sediments, or ground water. Phytoremediation may occur through contaminant degradation or containment, and in some cases, the plants are harvested and contaminants in the plant material are simply removed from the site. Growing trees on a contaminated site as a remediation method is an aesthetically pleasing, passive technique that can be used to cleanup sites with shallow or low to moderate levels of contamination. Phytoremediation can be used in place of, or in conjunction with, mechanical cleanup methods and works well for remediation of petroleum hydrocarbons, TNT or munitions waste, metals and other chemical compounds as well. How does phytoremediation work? Some of the methods that are being tested are described below. Phytoextraction also called phytoaccumulation, refers to the uptake and translocation of metal and chemical contaminants in the soil by plant roots in the above ground portions of the plants. Certain plants, called hyperaccumulators, absorb unusually large amounts of metals in comparison to other plants. Rhizofiltration is the adsorption of soil and groundwater contaminants onto, or into, plant roots. Rhizofiltration is similar to phytoextraction, but the plants are used primarily to address contaminated groundwater rather than soil. Phytostabilization is the use of certain plant species to immobilize contaminants in the soil and groundwater through absorption and accumulation by roots, or precipitation of the contaminants within the root zone of the plants (rhizosphere). This process reduces the mobility of the contaminants and prevents migration into the groundwater or air and reduces the bioavailability and thus entry into the food chain. Phytovolatilization is the uptake and transpiration of a contaminant by a plant, with release of the contaminant, or a modified form of the contaminant, into the atmosphere. In summary, phytoremediation is a new and exciting approach to cleaning up groundwater pollution and soil contaminants using different species of plants as the primary component. This method is lowcost, environmentally friendly and effective for a wide range of chemicals such as pesticides, solvents, crude oil, polyaromatic hydrocarbons, and metals as well.

Answer of crossword puzzle Across : 1. Hydrogen, 5. Basepairs, 7. Anatomy, 10. Enzyme, 12. Nucleus, 14. Sequence, 15. Dominant, 16. Proteins Down : 2. Nucleotide, 3. Antibodies, 4. Mutation, 6. Antigens, 8. Genome, 9. Recessive, 11. Gene, 13. Chromosome


Medicine • Medical genetics, genetic counselling

and genetic nursing • Gene testing and gene therapy • Organ transplantation, fertility and

reproduction • Public health • Pharmaceutical industry and suppliers:

– pharmacogenomics; – chemical, vaccine, medicine

development and production; – database development, operation and

use; and – communication and work with

regulatory agencies. Agriculture and Wildlife • Genetic modification of foods and seeds • Biopesticide and neutriceutical

development • Wildlife management: identification and

protection of endangered species • Authentication of consumables such as

wine and caviar Computational Biology (including bioinformatics • Database creation, data analysis,

modelling and data transfer • Supercomputing • Mathematics, statistics and actuarial

fields Engineering Disciplines • Bioprocessing chamber, vat design and

production • Toxic waste cleanup • Instrumentation development • Creation of new energy sources via

engineering and life science research • Biomedical engineering Business • Biosciences industry.

• Marketing and sales • Banking Law and Justice • Education • Patent specialities • Specialities in ethical, legal and social

issues • Gene and paternity testing • DNA forensics – in the laboratory, in the

field and in the courtroom History and Anthropology • Use of genetics to study population and

migration patterns • Study of inheritance over evolutionary time Military • Soldier identification • Pathogen (disease) identification • Biological and chemical warfare

protection • Radiation exposure assessment Space exploration • Research into space effects • Search for other life forms, evidence of

life Bench science • Sequencing of many organisms, including

humans • Data analysis and computation • Functional genomics • Proteomics • Human variation in health and disease • Microbial genetics • Environmental studies • Education Bioscience communication • Reporting, writing and editing • Website development and maintenance • Public relations • Marketing • Special events

SOME OF THE EXCITING CAREER IN BIOTECHNOLOGY


Summary As the India population and its demand for forest products increases, and land available for forests declines concreted efforts are needed to ensure sustainable forest production. Although the traditional practices of tree culture and tree breeding remain important in forestry activities, existing conventional breeding and production programmes are limited by the long growth cycle of forest trees and the problems breeders have to distinguishing between genetic traits and environmental effects. Biotechnology and its associated disciplines of biochemistry, physiology and genetics, play an important role in addressing some of these issues. Introduction World demand for forest products is increasing rapidly and shortages have been forecast to occur in the near future. Although traditional forest improvement programmes are helping in the industrialised world, efforts have lagged in the developing countries where the shortages will be most felt. Further, if indigenous forests, grasslands and floral biodiversity are to be preserved in India, commercial forestry production needs to be carefully managed. Consequently, there is an urgent need for research to increase the productivity (yield) and quality (superior wood, best stem form, uniformity, resistance to environmental stresses) of important forest trees, such as Eucalyptus, Pinus and Acacia spp.

Biotechnology, together with biochemistry, physiology and genetics, plays an important role in addressing these issues in tree improvement, selection of best genes, mass propagation and biodiversity conservation, to name a few.

BIOTECHNOLOGY AND BIODIVERSITY


Biotechnology techniques used in forestry breeding and production programmes Biotechnology is the management of biological systems for the benefit of humanity and it includes the conventional methods of plant breeding and cultivation. Additionally, “modern” biotechnology offers many new techniques for overcoming the constraints of large tree sizes, slow growth and reproduction. Some of the biotechnology methods to conserve & improve biodiversity are as follows : Micropropagation Currently, increased production of selected, superior tree varieties (genotypes) is being accomplished with the help of micropropagation. Costef f icient tissue culture techniques have been developed for most of the important forestry species: eucalyptus, pine and wattle. The process begins with cuttings taken from plants that are known to grow well. In a laboratory, these cuttings are induced to grow between 10 to 40 shoots by adding special growth hormones. Each shoot is removed, planted and induced (with different hormones) to grow roots. The rooted shoots are then acclimatised (hardenedoff) in soil in a greenhouse. Results indicate that growth rates, uniformity and quality of the micropropagated plants are


equal or better than those produced conventionally, by collecting and planting seeds. Somatic embryogeneis Somatic embryogenesis is the production of embryolike structures (baby plants) from nonreproductive (vegetative) cells. This technique offers a number of improvements over micropropagation. The most significant benefit is that it results in plantlets that have both root and shoot buds, so hormone treatments are not needed to develop shoots and roots. Also, plantlets developed from these somatic embryos have tap root systems. Cell suspension cultures A cell suspension culture consists of uniform and actively growing cells dispersed in a liquid culture medium. These tree cell suspensions offer an excellent tool for research and as recipients for new genes, inserted for genetic modification. These cell suspensions also offer a way to store tree types cost effectively for long periods in a frozen state. This helps breeders to keep gene banks of useful tree varieties and to keep a wide diversity of genes available for future breeding programmes. Germplasm conservation In common with agricultural crops, a tree breeder has to develop varieties for specific

growing areas without losing the genes from old varieties. These genes may be needed in the future to cope with changes in environment, growing methods, end use, pests or diseases. This can be achieved by storing plant material (tissues or cells) under minimal growth storage (temperature below 10°C, reduced oxygen supply, reduced nutrients, etc.) or frozen liquid nitrogen at –196°C (cryopreservation). Minimal growth storage provides a mediumterm solution only, as cultures lose their viability after a few months. Under

cryopreservation (at 196 °C) biological material may be stored indefinitely. As only very small pieces of tree material can survive the freezing stress, plant parts used for cryopreservation include buds, tissue cultured cell clumps, cell suspensions and pollen. Before freezing the plant tissues need to be prepared. This usually means treatment with

Micropropagation is the mass production of millions of plantlets in tissue culture. These are sold as improved planting material. They are of ten clones (genetically identical) and disease free.

Germplasm describes all the different varieties of a single organism.


cryoprotectants (e.g. glycerol, sucrose) that minimise freeze damage to the plant cells. The major benefit is the ability to store tree varieties without need for land, planting and management costs. Molecular markers In the breeding and selection of new tree varieties it can be difficult to see the improvements caused by gene rearrangements. Protein changes are used to identify some new characteristics, but DNA markers allow for the identification, or “fingerprinting”, of unique, individual genotypes (collection of genes that make a specific variety). At present, the most popular of the DNA marker system is the PCR based (polymerase chain reactionbased) DNA technique that is also used in animals, microbes and humans (e.g. forensics). This technique allows for positive identification of individuals and the comparison of gene similarities (relationships) between individuals. DNA profiles have already been established for many important tree species and the varieties within these groups. These DNA profiles (molecular markers) help breeders to identify which offspring from crosses are the best to keep in the breeding programme and which ones can be destroyed without losing important genes. As such, this technique saves money and time in forestry breeding programmes. Genetic transformation The ability to genetically engineer forest tree species has enormous potential applications for tree improvement. In recent years there have been a number of reports of successful gene transfer into tree species. Mostly these genes are for resistance to pests or to speed up growth, but some novel applications are also being tested, e.g. trees that can remove cadmium from contaminated soils. Genetically modified trees are undergoing field trials in the India, US, Canada, Australia and South Africa. No commercial releases have yet been approved. Concluding remarks Applied biotechnology has allowed important technical achievements worldwide over the past 10 years. Several of these techniques, such as tissue culture, already have direct applications in forestry breeding and production programmes in India. Cryopreservation of germplasm allows the storage of potentially tree varieties in the laboratory rather than in the field. Technologies such as DNA markers are being used to speed up breeding programmes as well as to identify novel genes in important tree species. The challenge that lies ahead will be to gain a better understanding of tree development, in order to maximise the benefits offered by biotechnology.


Activity : GM Tea British and Japanese researchers have tracked down the genetic source of caffeine in tea. Over the past few months the world’s press have reported on the tea cloning research carried out at the University of Glasgow, Scotland and Ochanomizu University in Japan. Having previously identified one of the key enzymes involved in the mechanism, the researchers have gone on to clone (isolate) a gene in tea responsible for caffeine biosynthesis. Most Camillia sinensis (or C. assamica) varieties grown contain about 2 to 3% (dry mass) of caffeine. There have also been varieties of tea propagated with naturally lower caffeine. However, the development of geneticallymodified tea plants would give rise to a cup of tea completely, and ‘naturally’ free of the substance. Caffeine is cited as the prime cause of many ailments, including irregular heart rhythms, gastrointestinal irritation, anxiety, insomnia and increased blood pressure. The news of naturally decaffeinated tea is thought to be welcomed by many tea drinkers who are sensitive to caffeine, or would prefer to limit intake. Improvements in food processing to strip the tealeaf of its caffeine have tried to satisfy the ‘decaf’ tea drinkers. Unfortunately, all attempts to decaffeinate the leaf have also altered flavour and aroma, and the beverage comes a poor second to the original. Years of plant breeding programmes in Africa, India, China and Japan have uncovered many new tea clones which have steadily improved the qualities of the tea beverage. Most new varieties of tea have been propagated in rich nations like Japan. Such producers have managed their tea stocks by a programme of continued investment in research. If tea drinkers accept the caffeinefree GM teas which are sure to follow, then growers would be forced to restock their gardens with the new caffeinefree clone. At a time when most tea gardens and plantations lack very basic investment, the costs associated with the mass replantings necessary to meet supply would be a daunting prospect, and one the tea industry could not afford.

1. Why is the genetically modified tea considered ‘naturally’ free of caffeine?

2. What is the difference between the way someone who is pro GM and another who is against GM would describe the term “natural”?


3. Why would GM caffeine free tea be considered better by tea lovers than teas that have had the caffeine removed after harvesting?

4. What are some of the effects of caffeine on the human body?

5. Do all people suffer from these side effects? Explain your answer.

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