Polymers and Life - Polymers and Enzymes

Question 1

what is an amino acid residue?

Answer 1

an amino acid when it is in a polypeptide chain/dipeptide

Question 2

what are the interactions between side chains in proteins?

Answer 2

id-id bonds

hydrogen bonds

ionic

covalent

Question 3

how are addition polymers formed?

Answer 3

electrophillic addition

starting material must contain a double bond

Question 4

what is the primary structure of proteins?

Answer 4

polypeptide chain of amino acids

Question 5

what holds the secondary structure of proteins together?

Answer 5

hydrogen bonds between N-H and C=O

Question 6

what are fibrous proteins usually made up of?

Answer 6

helices

Question 7

what are globular proteins usually made of?

Answer 7

both sheets and helices

Question 8

what are some examples of condensation polymers?

Answer 8

polyesters

polyamides (nylons)

polypeptides

Question 9

what must the monomers contain for condensation polymerisation?

Answer 9

two functional groups each

a carboxyl group

Question 10

what are polyamides typically formed from?

Answer 10

dicarboxylic acid + diamine

Question 11

what are polyesters usually made from?

Answer 11

carboxylic acid + alcohol

Question 12

how are nylons named?

Answer 12

nylon - number of carbon in diamine, number of carbon in dicarboxylic acid

Question 13

what is another name for a polyamide?

Answer 13

a nylon

Question 14

what reaction breaks down an ester?

Answer 14

hydrolysis

Question 15

which bond breaks in an ester during hydrolysis?

Answer 15

the C-O bond

Question 16

how quick is the hydrolysis of esters?

Answer 16

very slow without a catalyst

Question 17

why does the C-O bond in an ester break in hydrolysis?

Answer 17

it is a weak bond as the carbon is delta positive because of the C=O as well as the C-O

Question 18

what are the 2 conditions that esters can be hydrolysed in?

Answer 18

aqueous solution

aqueous alkaline solution

Question 19

what happens in the hydrolysis of esters in aqueous conditions?

Answer 19

carboxylic acid is formed

reversible reaction

water is the electrophile

Question 20

what happens when an ester is hydrolised in aqueous alkaline conditions?

Answer 20

a carboxylate salt is formed

not reversible

OH- is the electrophile

Question 21

what is the functional group of a carboxylate salt?

Answer 21

carboxylic acid but O- instead of OH

Question 22

what is the breakdown of amides called?

Answer 22

hydrolysis

Question 23

what are the 2 conditions that amides can be hydrolysed in?

Answer 23

alkaline solutions

acidic solutions

Question 24

what are the products of amide hydrolysis in acidic conditions?

Answer 24

amine salt + anion

Question 25

what acids are used in the hydrolysis of amides?

Answer 25

moderately concentrated hydrochloric or sulfuric

Question 26

what are the products of alkaline hydrolysis of amides?

Answer 26

carboxylate ion + amine formed

Question 27

what alkali is used in the hydrolysis of amides?

Answer 27

usually moderately concentrated NaOH

Question 28

why do the bonds formed between an enzyme and substrate need to be weak?

Answer 28

so that the substrate can leave the complex once the breakdown in complete

Question 29

what can affect the activity of enzymes?

Answer 29

pH

temperature

competition

substrate conc

Question 30

what bonds are usually formed between an enzyme and substrate at the active site?

Answer 30

hydrogen bonds or interactions between ionic groups

Question 31

what is the strength of the bonds formed between an enzyme and substrate?

Answer 31

relatively weak

Question 32

why are the bonds formed between an enzyme and substrate relatively weak?

Answer 32

so the products can leave the complex

Question 33

which type of inhibition do you need to know for chem?

Answer 33

competitive inhibition

Question 34

how do competitive inhibitors affect enzymes?

Answer 34

they bind to the active site but do not leave when the products are formed, denaturing the enzyme

Question 35

what are the two ways that pH can affect enzymes?

Answer 35

ionisable groups in the active site can react with or donate H+ ions, meaning it can’t interact with substrate the same

bonds in tertiary structure of the protein affected, shape breaks down and enzyme is denatured

Question 36

what is molecular recognition?

Answer 36

the way in which molecules interact in terms of intermolecular and non-covalent bonds

Question 37

what is a pharmacophore?

Answer 37

the part of a medicine molecule that allows it to have the desired effect

Question 38

what is the receptor site?

Answer 38

the part of the active site that forms bonds with the substrate

Question 39

what are some examples of molecular recognition?

Answer 39

antibodies + antigens

enzymes + substrates