Unit 2-Metabolic Pathways And Their Control

Question 1

What are metabolic pathways?

Answer 1

Metabolic pathways are enzyme-catalysed reactions within a cell.

Question 2

All of the metabolic pathways in an organism

Answer 2

Metabolism

Question 3

What are the two types of metabolic pathways?

Answer 3

Anabolic and catabolic.

Question 4

Metabolic activity which synthesises (builds up) complex molecules, requires energy.

Answer 4

Anabolic

Question 5

Metabolic activity which breaks down complex molecules, releases energy.

Answer 5

Catabolic

Question 6

A gap in the membrane caused by a channel forming protein.

Answer 6

Pore

Question 7

A protein found in the phospholipid membrane which carries molecules across via active transport.

Answer 7

Protein pump

Question 8

The energy required to start a chemical reaction

Answer 8

Activation Energy

Question 9

The region of an enzyme which allows the substrate to bind

Answer 9

Active Site

Question 10

The result of an enzyme catalysed reaction

Answer 10

Product

Question 11

The substance on which the enzyme acts.

Answer 11

Substrate

Question 12

The reaction can take place in more than one direction

Answer 12

Reversible

Question 13

Occurs when the active site changes shape to better fit the substrate after the substrate binds.

Answer 13

Induced fit

Question 14

The attraction of a substrate (high) or product (low) to the active site of an enzyme.

Answer 14

Affinity

Question 15

Three types of inhibition

Answer 15

Competitive inhibition

Non-competitive inhibition

Feedback inhibition

Question 16

Competitive inhibition

Answer 16

Inhibitor molecule binds to the active site of the enzyme and stops the substrate from binding

Question 17

What property of a competitive inhibitor allows it to compete with the substrate?

Answer 17

They have a similar molecular shape allowing them to bind to the enzyme’s active sites.

Question 18

How can competitive inhibition be reversed?

Answer 18

By increasing substrate concentration.

Question 19

Non-competitive inhibition

Answer 19

Inhibitor does not bind to the active site but does bind to a different part of the enzyme and changes the active site shape.

Question 20

Will increasing substrate concentration reverse non-competitive inhibition?

Answer 20

No

Question 21

Feedback inhibition

Answer 21

End product in a metabolic pathway binds to an enzyme at the start of the pathway stopping metabolic pathway