Unit 1 Flashcards
Biological Molecules
define polymer
molecules formed when multiple monomers are joined together
define monomer
smaller, basic units that join together to form larger molecules
what happens in a condensation reaction?
formation of a chemical bond between two molecules involving the elimination of a water molecule
what happens in a hydrolysis reaction?
breaking of a chemical bond between two molecules through the use of a water molecule
give three examples of monomers
monosaccharides, amino acids, nucleotides
name the three monosaccharides
glucose, galactose, fructose
name the bond that forms between two monosaccharides
glycosidic bonds
give the molecular formula of a monosaccharide
C6H12O6
what elements are in carbohydrates?
C, H, O
name three disaccharide’s
Maltose, sucrose, lactose
Maltose is formed in the condensation reaction between…
two (Alpha) Glucose
Sucrose is formed in the condensation reaction between…
(Alpha) Glucose and fructose
Lactose is formed in the condensation reaction between…
(Alpha) Glucose and galactose
describe the difference between between alpha and beta glucose
hydroxyl group is reversed (alpha has OH on the bottom of the right side)
give the molecular formula of a disaccharide
C12H22O11
what storage molecule do plants use
starch (some glycogen)
what storage molecule do animals use
glycogen
what are the two types of starch
amylose and amylopectin
give three properties that make starch useful
insoluble - no effect on water potential
large - doesn’t diffuse out of the cell
branched - quick hydrolysis of glucose
describe the structure (and function) of amylose
alpha-helix shape with hydrogen bonds between (makes it compact), 1-4 glycosidic bonds (no branching)
describe the structure (and function) of amylopectin
branched (many terminal ends for the hydrolysis of glucose), 1-4 and 1-6 glycosidic bonds (alpha glucose)
describe the structure (and function) of glycogen
branched (many terminal ends for the hydrolysis of glucose), 1-4 and 1-6 glycosidic bonds (alpha glucose)
describe the structure of cellulose
1-4 glycosidic bonds between beta glucose forming straight chains, microfibrils are formed due to hydrogen bonds
what is the test for reducing sugars
Benedict’s reagent, heat in water bath, positive result; blue to green to brick red
what is the test for non-reducing sugars (sucrose)
heat and acid (HCl), then the Benedict’s test
what is the test for starch
iodine, positive result; brown to black
difference between saturated and unsaturated fats
unsaturated have double C-C bonds
why are unsaturated lipids liquid at room temperature
double bonds mean unsaturated can bend and cannot become compact
what does a triglyceride consist of
1 glycerol and 3 fatty acids
what does a phospholipid consist of
1 phosphate group, 1 glycerol and 2 fatty acids
what is the name of the bond between glycerol and fatty acids
ester bond
why can phospholipids form a bilayer/micelles
they have a hydrophilic (polar) head and hydrophobic (non-polar) tails
describe the emulsions test
shake with ethanol, add water, positive result; cloudy-white colour
give the structural formula of an amino acid
NH2CH(R)COOH
what are different amino acids defined by
the R group
how many amino acids are there
20
name the bond between amino acids
peptide bond
whats the difference between a dipeptide and polypeptide
di is 2 and poly is more than
describe the primary structure
the sequence of amino acids (peptide bonds)
describe the secondary structure
either a beta-pleated sheet or alpha-helix (hydrogen bonds)
describe the tertiary structure
folded into a 3D shape (hydrogen, ionic, disulfide)
describe the quaternary structure
multiple polypeptides (sometimes with a prosthetic group)
what is the difference between a fibrous and globular protein
globular are usually compact and have a purpose, fibrous are repeating units (mutation is less likely) that form fibers
describe the biuret test
add biuret solution, positive result; blue to purple
describe an enzyme
biological catalyst that lowers activation energy, 3D tertiary globular structure
describe the induced fit model
the enzyme binds the the complementary substrate, forming an enzyme-substate-complex. the active site alters to fit the substrate
whats the main difference between the ‘lock and key’ and ‘induced fit’
in the ‘lock and key’ the enzyme and substrate are the exact same shape
effect of temperature on enzyme action
rate of reaction increases as kinetic energy is increased, collision is more likely (more enzyme-substrate-complexes) after optimum hydrogen bonds break and the enzyme denatures (less enzyme-substrate-complexes)
effect of pH on enzyme action
as pH moves away from optimum H+ and OH- cause the ionic bonds to break and the enzyme to denature (less enzyme-substrate-complexes)
effect of enzyme concentration on enzyme action
originally increases (more enzyme-substrate-complexes) until substrate become a limiting factor and rate of reaction plateaus (less enzyme-substrate-complexes)
effect of substrate concentration on enzyme action
originally increases (more enzyme-substrate-complexes) until active sites are filled and rate of reaction plateaus (less enzyme-substrate-complexes)
describe a competitive inhibitor
binds to active site so enzyme-substrate-complexes can’t form
describe a non-competitive inhibitor
binds to the allosteric site and alters the enzymes active site so enzyme-substrate-complexes can’t form
what type of replication is in DNA
semi-conservative replication
describe DNA replication
DNA helicase breaks hydrogen bonds between complementary bases, complementary nucleotides are joined to the template strand by DNA polymerase, 2 identical strands form
describe the structure of a nucleotide
phosphate, pentose sugar and a nitrogenous base (adenine, thymine, cytosine, and guanine)
describe the structure of ATP
adenine, ribose sugar, 3 phosphate groups
properties of ATP
small amounts of energy released at a time, easily resynthesised by ADP and Pi
give properties of water
used in metabolic reactions, solvant, polar, high specific heat capacity and water of vaporisation
purpose of phosphate ions
in ATP, RNA, DNA
purpose of Fe
prosthetic group of haemoglobin, carries oxygen
