Enzymes Q

Question 1

Explain how the shape of an enzyme molecule is related to its function

Answer 1

• specific 3D tertiary structure
• specific complementary shape
• substrate can bind to active site

Question 2

An enzyme catalyses only one reaction. Explain why

Answer 2

• enzyme has active site

- only 1 substrate fits the active site

Question 3

Describe the induced-fit model of enzyme action

Answer 3

• before reaction, active site not complementary to substrate
• shape of active site changes as substrate binds as E-S complex forms
• bending bonds in substrate leading to reaction

Question 4

Explain how enzyme models have changed over time

Answer 4

1 - lock and key, 1 enzyme, 1 substrate

2 - induced fit - 1 enzyme, multiple substrates, more flexible, active site moules

Question 5

Compare 2 models fo enzyme action

Answer 5

Lock and key - active site rigid, active site an exact fit with substrate, substrate binds to active site and enzymes break bonds (catabolic)

Induced fit - active site rigid, active site moulds around substrate, binding of substrate to active site causes change

Question 6

Give an example of an intracellular process and how it could effect a cell

Answer 6

Respiration - ATP production

Question 7

Give an example of an intracellular process and how it could effect a whole organism

Answer 7

Protein synthesis - link to cell cycle, mitosis and growth

Question 8

Give an example of an extracellular process and how it could effect a cell

Answer 8

Digestion - hydrolysis of large insoluble molecules into small soluble molecules so they can be absorbed

Question 9

Give an example of an extracellular process and how it could effect a whole organism

Answer 9

Blood clotting process