biological reactions are regulated by enzymes

Question 1

define the lock and key theory

Answer 1

each enzyme active site is complementary with its substrate

Question 2

define induced fit theory

Answer 2

active site not exact shape. substrate changes slightly to active site. this is proved by lysozyme

Question 3

how do enzymes work

Answer 3

they lower the activation energy

Question 4

define a competitive inhibitor

Answer 4

structurally similar to the substrate molecule - fit in substrate.

Question 5

what prevents competitive inhibitors working

Answer 5

increases in substrate concentration will decrease the effect of the inhibitor as the enzyme most likely to collide with substrate

Question 6

define non competitive inhibitors

Answer 6

binds to the allosteric site to denature enzyme so substrate can fit into active site - no enzyme substrate complex.

Question 7

what are advantages of immobilized enzymes

Answer 7

• enzyme does not contaminate
• enzyme can be recovered and reused
• only small amounts of enzymes needed
• more resilient to temperatures and pH
• can use more than one enzyme

Question 8

what is a buffer

Answer 8

a solution that resists pH changes maintaining a stable environment preventing denaturization.

Question 9

what is an immobilized enzyme

Answer 9

fixed bound or trapped on an innert matrix

Question 10

what are some uses of enzymes

Answer 10

• used to make lactose intolerant milk
• biosensors

Question 11

why are immobilized enzymes inert

Answer 11

prevents them from moving in the reaction and keeps them stable