2.1 Criteria

Question 1

Define Metabolism:

Answer 1

Is the total set of reactions in a cell.

Question 2

What does it mean by ‘Metabolic pathways are intergated’?

Answer 2

Meaning different pathways are inter-linked.

Question 3

What catalyses metabolic reactions within the cells?

Answer 3

series of enzyme catalysed reactions

Question 4

What kind of steps do metabolic pathways have?

Answer 4

Reversible and irreversible steps

Question 5

What is the name of the routes that metabolic pathways have to the same intermediate or end product?

Answer 5

Alternative routes

Question 6

Define anabolic reactions:

Answer 6

Energy-requiring reactions which build up large molecules from small molecules

Question 7

Define catabolic reactions:

Answer 7

Energy-yielding reactions which break down large molecules into small molecules

Question 8

Why might some membranes have protein pores?

Answer 8

To allow or restrict the passage of molecules through the membrane

Question 9

Why might some membranes have protein pumps?

Answer 9

To move molecules across the membrane, and they require energy to do this

Question 10

Why might some membranes have enzymes embedded in them?

Answer 10

To catalyse specific biochemical reactions

Question 11

Metabolic pathways may be controlled by the presence or absence of what?

Answer 11

Enzymes

Question 12

Metabolic pathways may be controlled by the regulation of what?

Answer 12

Key enzyme activity

Question 13

What is meant by the induced fit?

Answer 13

How the active site of an enzyme may change shape to better fit the substrate as the substrate binds

Question 14

What does an enzyme do to the activation energy for a reaction?

Answer 14

Lowers it

Question 15

Does a substrate have a high or a low affinity for an active site?

Answer 15

High

Question 16

Does a product have a high or a low affinity for an active site?

Answer 16

Low (this allows it to leave)

Question 17

As the substrate concentration increases the…

Answer 17

Rate of reaction increases but then becomes constant

Question 18

What do competitive inhibitors do?

Answer 18

Bind at an active site preventing the substrate from binding

Question 19

How can competitive inhibitors be reversed?

Answer 19

By increasing substrate concentration

Question 20

What do non-competitive inhibitors do?

Answer 20

Bind away from the active site but this has the effect of changing the shape of the active site, preventing the substrate from binding

Question 21

When does feedback inhibition occur?

Answer 21

Occurs when the end product of a metabolic pathway reached a critical concentration

Question 22

What does feedback inhibition prevent further synthesis of?

Answer 22

The end product in a metabolic pathway