Enzymes

Question 1

what is an enzymes tertiary structure?

Answer 1

globular proteins

Question 2

what are scaffolding proteins?

Answer 2

the site of multiple enzymes working together to complete the same task

Question 3

is the active site a small or large section of an enzyme?

Answer 3

a small portion

Question 4

what is the equation of the active site?

Answer 4

binding site + catalytic site = active site

Question 5

what is the activation energy?

Answer 5

the initial investment of energy to being the reaction and form the unstable intermediate

Question 6

what is the transition state?

Answer 6

the unstable intermediate

Question 7

how can the transition state occur?

Answer 7

adding heat

catalysts

Question 8

what does the activation energy do to the viability of the reaction?

Answer 8

it makes the production of the final product energetically favorable

Question 9

what happens to the activation of the reaction when an enzyme is used?

Answer 9

the activation energy is much lower

Question 10

can enzymes change an endergonic reaction to an exergonic reaction?

Answer 10

no

Question 11

are enzymes specific to reactions?

Answer 11

yes

Question 12

how can enzymes lower the activation energy?

Answer 12

re-orientating substrates to increase efficiency allowing them to react
distorting substrate bonds allowing them to move to the transition state
adjusting the micro-environment of the substrates to allow substrates to interact and form product bonds.

Question 13

what are cofactors?

Answer 13

non-protein chemicals that can aid biological reactinos

Question 14

what are examples of inorganic cofactors?

Answer 14

pH, temperature and phosphorylation

Question 15

what are examples of organic cofactors?

Answer 15

co-enzymes, often essential nutrients and minerals

Question 16

what are cosubstrates?

Answer 16

transient cofactors

Question 17

what is the equation for inactive + cofactor = whole active enzyme

Answer 17

apoenzyme+cofactor=whole active enzyme

Question 18

what is a competitive inhibitor?

Answer 18

something that binds to the active site blocking the substrate

Question 19

what is an example of a competitive inhibitor?

Answer 19

penicilin

Question 20

what is a non-competitive inhibitor?

Answer 20

something that changes the shape of the binding site allowing the enzyme to react with different substrates

Question 21

what is an example of a non-competitive inhibitor?

Answer 21

lead - where the inhibitor fully reduces the rate of reaction the enzyme is capable of

Question 22

which can be out-competed - competitive or non-competitive inhibitors?

Answer 22

competitive inhibitors can be out-competed by increasing substrate concentration. this isn’t always possible with non-competitive inhibitors

Question 23

what is an example of an irreversible inhibitor?

Answer 23

toxins and poisons e.g. CO

Question 24

what are reversible inhibitors?

Answer 24

allosteric - usually w/ enzymes with multiple active sites and different substrates.

Question 25

what is an example of allosteric inhibitors?

Answer 25

co-operative binding e.g. O2 and haemoglobin