what is it that makes up an atom? essential question 10.8.2007 biochemistry
TRANSCRIPT
What is it that makes up an atom?
Essential Question
10.8.2007
Biochemistry
Matter• Properties
– physical property• description of shape, mass, volume• melting point, boiling point
– chemical property• structure of molecules which make up
substance• how substance reacts with another
Biochemistry
Matter• Elements
– element • a substance that can not be broken
down into a simpler substance– 25 elements are essential to life
• CHNOPS – 6 greatest
Biochemistry
Matter• atom
– smallest particle of an element that has the characteristics of that element
Biochemistry
Atoms• atom structure
– nucleus• center, contains neutrons & protons
– neutrons mass (1.009u)• carries no charge,
neutral = n0
– protons (1.007u)• carries a positive charge
= p+
Biochemistry
Atoms• atom structure
– electron (5.486 x 10-4u) • electrons carry
a negative
charge = e-
Biochemistry
Atoms• atom structure
– electron • electrons orbit nucleus in separate
energy levels or clouds
Biochemistry
AtomsBiochemistry
Atoms• periodic table
– atomic number• number of protons
– atomic mass• total mass of protons, neutrons, &
electrons– atomic symbol
• 1or 2 letter symbol for element
Biochemistry
symbol
How are
covalent and ionic bonds
different?
What is an example of each?
Essential Question
10.9.2007
Biochemistry
chemical bonds• chemical bond
– two or more atoms chemically bonded togetherex: oxygen gas, water, glucose
• molecular formula– uses atomic symbols to represent atoms
bound together in a compound
ex: O2,
H2O,
C6H12O6
Biochemistry
chemical bonds• covalent bond
– atoms share electrons
ex: water, sugars, proteins• ionic bond
– attractive force between ions of opposite charge
Biochemistry
chemical bonds
covalent bond
ionic bond
Biochemistry
What ions are released by
an acid in water? By a base?
Essential Question
10.10.2007
Biochemistry
Mixtures and solutions• mixture
– combination of substances in which individuals retain individual propertiesex: mixed sugar and sand,
oil and water• solution
– mixture of one or more solutes are evenly distributed in a solvent
ex: salt in water
Biochemistry
Mixtures and solutions• solution
– solute• substance which dissolves ex: sugar
– solvent• holds dissolved substance ex: water
– the greater the solute = greater the concentration
Biochemistry
Acids and bases• pH
– measure of how acidic or basic a solution is• acid
– forms hydrogen ions (H+) in water– pH below 7
• base– forms hydroxide ions (OH-) in water– pH above 7
Biochemistry
Acids and basesBiochemistry
Water • polar molecule
– molecule with uneven distribution of charge
– water is polar, O atom pulls e-’s from H atoms
Biochemistry
Water • hydrogen bond
– weak attraction between hydrogen and oxygen atoms in different molecules
Biochemistry
Water • properties of water
– water resists temperature change– water expands when it freezes – cohesion
• water molecules attracted to each other– adhesion
• water molecules attracted to sides of container
Biochemistry
Water • properties of water
– water resists temperature change
Biochemistry
Water • properties of water
– water expands when it freezes
Biochemistry
Water – cohesion
• Water molecules attracted to each other
Biochemistry
Water – adhesion
• Water molecules attracted to sides of container
Biochemistry
More compounds– isomer
• compounds with same number elements but different structure
Biochemistry
More compounds– monomer
• Small molecule that can be bound to other monomers to form polymers
– polymer• larger molecule formed from smaller
subunits
Biochemistry
More compounds– monomer
• Small molecule that can be bound to other monomers to form polymers
– polymer• larger molecule formed from smaller
subunits
Biochemistry
More compounds– polymer
• larger molecule formed from smaller subunits
Biochemistry
More compounds– polymer
Biochemistry
Macromolecules– carbohydrates
• used by cells to store and release energy
• 1:2:1C:H:O
ex: glucose C6H12O6
Biochemistry
Macromolecules – carbohydrates
• monomer → polymer
Biochemistry
monosaccharide glucose, fructose
disaccharide sucrose
polysaccharide cellulose, glycogen
Macromolecules– carbohydrates
• monomer → polymer
monomer polymer
Biochemistry
monosaccharide glucose, fructose
disaccharide sucrose
polysaccharide cellulose, glycogen
Macromolecules– carbohydrates
• monosaccharides
Biochemistry
Macromolecules– carbohydrates
• disaccharides
Biochemistry
Macromolecules– carbohydrates
• polysaccharides
Biochemistry
verbascose
What are the components of a
lipid and of a protein?
Essential Question
10.17.2007
Biochemistry
Macromolecules– lipids
• used for energy storage, insulation, protection
ex fats, waxes and oils• nonpolar, does not dissolve in water• contains CHO
Biochemistry
Macromolecules– lipids
• glycerol head• 3 fatty acid tails
Biochemistry
Macromolecules– lipids
• glycerol
head• 3
fatty acid
tails
Biochemistry
Macromolecules– lipids
• large proportion of C–H bonds– saturated fats
» C atoms in tail all have single (C–C) bonds
– unsaturated fats» C at least 1 double bond (C=C)
in tail
Biochemistry
Macromolecules– lipids
Biochemistry
Macromolecules– Proteins
• used for growth, maintenance, and repair
• used as structure for tissues and organs
• contain CHON
Biochemistry
Macromolecules– proteins
• polymer of amino acids– formed using peptide bonds
(covalent bond)
Biochemistry
Macromolecules– proteins
• amino acids (monomer)
Biochemistry
Macromolecules– proteins
• peptide bonds– bond between
amino acids
Biochemistry
Macromolecules– proteins
Biochemistry
Macromolecules– proteins
Biochemistry
Macromolecules– proteins
• enzyme– increase rate of metabolic
reactions– induced fit (lock and key)
mechanism
Biochemistry
Macromolecules– proteins
• enzyme– induced fit (lock and key)
Biochemistry
Macromolecules– nucleic acids
• stores cellular information• polymer of nucleotides• contains CHONP
Biochemistry
Macromolecules– nucleic acids
• DNA– genetic information for whole cell
• RNA– copies DNA to form protein
Biochemistry
Macromolecules– nucleic acids
• polymer of nucleotides
Biochemistry
Macromolecules– nucleic
acids
Biochemistry
Reactions– chemical equations
• 2H2 + O2 → 2H2O
Biochemistry
Reactions– chemical equations
• 2H2 + O2 → 2H2O
products
reactantants
Biochemistry
Reactions– chemical equations
• 2H2 + O2 → 2H2O
• # of atoms on each side of reaction must be balanced
• coefficients must be balanced
__ C6H12O6 → C12H22O11 + H2O
Biochemistry
Reactions– chemical equations
• dehydration synthesis (condensation reaction)– two subunits make polymer – water is released
2C6H12O6 → C12H22O11 + H2O
Biochemistry
Reactions– chemical equations
• dehydration synthesis
Biochemistry
Reactions– chemical equations
• hydrolysis– H2O splits bond
– two subunits created– C12H22O11 + H2O → 2C6H12O6
Biochemistry
Reactions– chemical equations
• hydrolysis
Biochemistry
Reactions– enzymes
• lowers activation energy• acts as catalysts, speeds up rate of
reaction• induced fit model (lock and key)
Biochemistry
Reactions– enzymes
• substrate– changed after released by enzyme
• enzyme– active site
» where substrate binds to enzyme
» can be used over and over
Biochemistry
Reactions– enzymes
Biochemistry
Reactions– enzymes
Biochemistry