biochemistry. no carbon inorganic non-living things small molecules water salts acids bases low...
TRANSCRIPT
Biochemistry
Biochemistry
No Carbon
Inorganic
Non-Living Things
Small MoleculesW
ater
Sal
ts
Aci
ds
Bas
es
Low Energy
Biochemistry
Has Carbon
Organic
Living Things
Large MoleculesC
arb
oh
ydra
tes
Lip
ids
Pro
tein
s
Nu
clei
c A
cid
s
High Energy
• Do not contain Carbon (carbon dioxide is an exception)
• Not made or created by living things
• Typically small ionically bonded molecules
• Examples: Water, Salts, Acids, Bases
Inorganic CompoundsInorganic Compounds
Organic CompoundsOrganic Compounds
• Contain Carbon as primary “backbone element”
• Are molecules that are made from and was once part of living things
• Typically called “macromolecules” due to their large size and number of atoms
• Mostly covalently bonded molecules (great deal of stored energy in their bonds)
• Examples: Carbohydrates, Lipids, Proteins, Nucleic Acids
Inorganic Molecules
• Water• Salts• Acids• Bases
1. Water recall….
• Polarity
• Hydrogen bonds
• Transparent
• Universal Solvent
• Cohesion
• Surface Tension
• Adhesion
• Capillary action
• Albedo Effect• Relative Humidity
• Water Cycle
• Density
• Boiling Point, Freezing Point
• Specific Heat, Latent Heat
• High Heat Capacity
2. Salts, Minerals, Electrolytes
• Important ionically bonded compounds found in living things needed for nerve impulses, muscle contraction, and general cellular functioning
• Most body fluids contain “salt” solutions.
• According to many biologists, this is due to life evolving in the ocean
3. Acids
• Acids are ionic substances that dissociate in water to produce hydrogen ions and some other negative ion
Dissociate = split into ions when placed in water
HCl H+ + Cl-
Hydrogen Ion
Characteristics of Acids …
• Corrosive
• Taste Sour
• Citric fruits (Citric Acid)
• Hydrochloric Acid = HCl
• Sulfuric Acid = H2SO4
• Acetic Acid = Vinegar
Examples of Acids …
4. Bases
• Bases are ionic substances that dissociate in water to produce hydroxide ions and some other positive ion.
NaOH Na+ + OH-
Hydroxide Ion
Characteristics of Bases…
• Feel Slippery
• Taste Bitter
Examples of Bases…• Cleaning Products
• Bleach
• NaOH = Sodium Hydroxide
• Baking Soda
Acid/Base Solutions
• Acidity or alkalinity (base) is a measure of the relative amount of H+ and OH- ions dissolved in a solution. Neutral Solutions have an equal number of H+ and OH- ions.
The pH Scale compares the relative concentration of H+ ions and OH- ions
Each pH unit is 10X stronger or weaker !
Litmus Paper• Simple paper test to determine if a substance is acidic or basic
Acid Base Neutralred stays red red turns blue red stays redblue turns red blue stays blue blue stays blue
pH Paper
• Color test to determine the actual pH of a solution.
Buffer• A Solution/chemical that will
prevent dramatic changes in pH.
** Limestone: a natural buffer **
Organic Molecules
• Carbohydrates
• Lipids
• Proteins
• Nucleic Acids
Biological Molecules … you are what you eat.
The Carbon Atom: “The Backbone Atom”
Carbon has 4 valence electrons – bonds with up to four other atoms (H, O, N, or another C)
• Most organic compounds from carbon chains
• Some may form rings of Carbon atoms as well
C C C C C
Recall ……
Formation: Repeating small units combine to
make larger structures
Small building units are called monomersA monomer is like an individual brick
A series of monomers linked together forms a polymer.A polymer is a brick wall
Building Organic Macromolecules
• Monomers link together in a chemical reaction called Dehydration Synthesis (Condensation Reaction)
Water is removed to build larger molecules from smaller ones – covalent bonds will form
Monomer Monomer Monomer Monomer
Water Water Water
Breaking Down Organic Compounds
• Polymers break apart in a chemical reaction called Hydrolysis
Water is added to break down large molecules into smaller ones – covalent bonds will break.
Monomer
Monomer
Monomer
Monomer
WaterWaterWater
Carbohydrates• Cells of the human body obtain most of
their energy from carbohydrates
• Made of Carbon, Hydrogen, and Oxygen in a ration of 1:2:1
• Types: Monosaccharides
Disaccharides
Polysaccharides
Monosaccharides• Single Sugars • These molecules are considered monomers of all the
other larger carbohydrates• Examples:
Glucose: only sugar used for energyFructose: Sugar found in fruit (sweetest)Galactose: Sugar found in milk
• All are Isomers = same formula (C6H12O6), different structure
Disaccharides• Double Sugar Molecules
• Sucrose is composed of glucose and fructose and is transported within plants. (Table Sugar)
• Lactose is composed of
galactose and glucose and
is found in milk.
• Maltose is two glucose molecules; forms in digestive tract of humans during starch digestion.
Polysaccharides
• Large sugars made of many monosaccharide units
• Starch is straight chain of glucose molecules with few side branches.
Function: Energy storage molecule in plants
• Glycogen is highly branched polymer of glucose with many side branches; called "animal starch," it is storage carbohydrate in the liver of animals.
• Cellulose is glucose bonded to form microfibrils; primary constituent of plant cell walls.
• Chitin: A tough, protective, semitransparent substance, primarily a nitrogen-containing polysaccharide, forming the principal component of arthropod exoskeletons and the cell walls of certain fungi.
Lipids• Lipids are large,
NONPOLAR organic molecules that do not dissolve in water
• Lipid molecules have a HIGHER ratio of carbon and hydrogen atoms to oxygen atoms than carbohydrates.
Example: C57 H110 O6
• Lipids store energy efficiently. They have large numbers of Carbon to Hydrogen bonds, which store more energy than Carbon to Oxygen bonds common in other Organic Compounds.
• Only used for energy when the body has no other immediate energy source.
TRIGLYCERIDES • Three Molecules of Fatty Acids joined to One
Molecule of Glycerol.
• Water is removed by the OH of Glycerol and the H from each fatty acid chains.
Saturated Fats• SATURATED FATS
• NO DOUBLE BONDS BETWEEN THE CARBONS
• “straight” molecule
• SATURATED FATS ARE USUALLY SOLID AT ROOM TEMPERATURE, AND MOST COME FROM ANIMAL PRODUCTS
Unsaturated Fats• UNSATURATED FATS
• SOME DOUBLE BONDS between Carbons.
• This creates a “bend in the molecule.”
• UNSATURATED FATS ARE USUALLY LIQUID AT ROOM TEMPERATURE, AND
MOST COME FROM PLANT PRODUCTS
Phospholipids• Similar to triglycerides, but
contain a phosphate group in place of the third fatty acid chain.
• The phosphate group is polar and capable of interacting with water.
• Membranes that surround cells and surround many cell structures are primarily phospholipid bilayers
Steriods• Classified as lipids
due to its non-polar nature (will not dissolve in water)
• Steroids have a backbone of 4 carbon rings
• Cholesterol is the precursor of several other steroids including several hormones
Dehydration Synthesis in Lipids
Proteins• Proteins are organic compounds composed mainly of
C, H, O, N, and sometimes S.
• They are the most abundant organic compound in the body. (50%)
Common Proteins• Structural proteins include
keratin, which make up hair and nails, and collagen fibers, which are elastic fibers in the skin.
• Actin and Myosin proteins are found in muscle tissues
• Enzymes are functional proteins that act as catalysts
• Hemoglobin is a protein found in blood
• Insulin is a protein that helps regulate blood sugar
• Defense: Antibodies help fight foreign microbes in the body
Structure of Proteins
• Amino Acids are the monomers that condense to form proteins.
• There are 20 different amino acids
• All are similar in structure: only the R-Group is different among the twenty;
gives each different properties
R–G
rou
ps a
re in
blu
e
Dehydration Synthesis of Amino Acids
• A peptide bond forms when the amino group of one amino acid bonds to the carboxyl group of another amino acid
• One water molecule is removed in a dehydration synthesis reaction to form a dipeptide.
• A polypeptide (protein) is the result of many linked amino acids.
Primary Structure Amino acids in a straight chainSecondary Structure Folding and/or coiling; caused by hydrogen bonding between amino acids
Tertiary Structure Additional folding into a more complex structure; more H- bondsQuaternary Structure Involves several subunits together Many polypeptides join to form a
functional protein
Denatured Proteins
• Denaturation: Protein shape is altered
• Once a protein is denatured, it loses its ability to perform its function
• Examples: Acid causes milk protein to “curdle”Heat causes egg white protein to coagulate
Special Proteins: Enzymes• Often serve as catalysts - Speed up the rate of
chemical reactions in living things without being used up in the process
• Enzymes are shaped specifically to fit a certain substrate (chemical that the enzyme works on).
• Fit together at the active site of the substrate like a “Lock & Key”
• This new complex helps a reaction occur faster.
• Enzymes can be re-used many times
Nucleic Acids: DNA & RNA• Very large molecules
that store important information in cells (genetic/heredity info)
• Elements: C, H, O, N, P
• Deoxyribonucleic Acid = DNA; contains info that is essential for all cell functions
• Ribonucleic Acid = RNA; transmits genetic info for the making of proteins
Structure of Nucleic Acids
• Both DNA and RNA are polymers composed of thousands of linked monomers called Nucleotides
• Nucleotides are composed of three parts …1) 5 Carbon Sugar
2) Phosphate Group
3) Nitrogen Base
Polymer structure
• Nucleotides bond to one another by dehydration synthesis to form large polymers
• DNA is composed of two strands that twist into a helix
• RNA is composed of a single strand and forms different shapes, but not helices