Enzymes

Question 1

Enzymes are what type of biomacromolcule?

Answer 1

Proteins

Question 2

Define enzymes

Answer 2

Protein molecules that catalyse chemical reactions

Question 3

What substance is energy dervied from

Answer 3

ATP

Question 4

Chemical reaction of ATP

Answer 4

ATP —–> ADP + Pi

Question 5

Define anabolic reactions

Answer 5

Form larger compounds from smaller units

Question 6

Anabolic reactions are also……

Answer 6

endergonic

Question 7

What do engergonic reactions require?

Answer 7

energy

Question 8

Define Catabolic reaction

Answer 8

Break down larger compound in a smaller one

Releases energy

Question 9

What are catabolic reactions also……

Answer 9

exergonic

Question 10

What do exergonic reactions release?

Answer 10

energy

Question 11

Define Activation energy

Answer 11

The minimum energy required for a reaction to occur

Question 12

How do catalyst work

Answer 12

Increases the rate of reaction by lowering the activation energy

Question 13

Explain enzyme specifiity

Answer 13

They are highly specfic as each enzyme acts on one substrate, tthis is due to the specifc shape of the active site on the enzyme matching the shape of the substarte molecule

Question 14

what is an enzyme substrate complex

Answer 14

When the substrate is bound to the enzymes active site

Question 15

What do enzymes and substartes need to be?

Answer 15

Complementary

Question 16

What are the molecules enzymes work on

Answer 16

Substrates

Question 17

Explain the lock and key theory

Answer 17

States that the active site fits exactly onto the substarte that it acts on

Question 18

Explain the induced fit model

Answer 18

States that the active site is slightly altered to match the substrate (enzyme changes shape)

Question 19

Explain what cofactors are and their role

Answer 19

inorganic or organic compunds that are nesscary to pbe present for the function of particular enzymes

Question 20

Define coenzymes

Answer 20

Organic factors that are nesscary for the action of certain enzymes. Changed in the reaction they take part in and cannot be used again

Question 21

What do all enzymes end in

Answer 21

ase

Question 22

Define competitive inhibitors

Answer 22

Compounds that compete for the active site and may mimic it, thus ceasing the enzyme from working as the substrate can no longer bind there

Question 23

Define Non-competiive inhibitors

Answer 23

Chemical compounds that bind to an allosteric site and alter confirmation of the enzymes active site so that the reaction cannot proceed.

Question 24

What happens if the temperature that the enzymes environment is in is too low

Answer 24

• Molecule activity is lower and moving slower
• Hence colliding with substrate molecules less frequently
• Enzyme substrate complexes are less likely to form
• Therefore reaction rates fall

Question 25

What happens if the temperature that the enzymes environment is in is too high

Answer 25

• Heat will begin to break down the bonds in the enzyme
• Cause conformation shape to be change and the active site to be destroyed, enzymes have become denatured
• Enzyme-substrate complexes can no longer form as they are no longer complementary
• Therefore reaction rates fall

Question 26

What does a change in pH do to the enzyme?

Answer 26

Causes a change in the enzymes active site

-However can be reversed

Question 27

Explain how enzyme concentration can affect the rate of the reaction

Answer 27

If the concetration of the enzyme is increased so is the rate of the reaction as more enzyme subtrate complexes are being formed

Question 28

Explain the increase of subtrate concentration

Answer 28

• Initially increase the rate of reaction
• Untill all of the active sites are occupied/saturated
• When this happens the rate becomes constant