Respiration

Question 1

Stages of aerobic respiration

Answer 1

1) glycolysis
2) link reaction
3) krebs cycle
4) oxidative phosphorylation

Question 2

Location of glycolysis

Answer 2

Cytoplasm

Question 3

Glycolysis

Answer 3

Substrate level phosphorylation
- 2 ATP molecules add 2 phosphate groups to glucose
glucose phosphate splits into two triose phosphate (3C) molecules
both TP molecules are oxidised
(reducing NAD) to form 2 pyruvate molecules (3C)
releases 4 ATP molecules

Question 4

Coenzymes

Answer 4

A molecule which aids / assists an enzyme
NAD and FAD in respiration both
gain hydrogen to form reduced
NAD and reduced FAD
NADP in photosynthesis gains
hydrogen to form reduced NADP

Question 5

Coenzymes

Answer 5

A molecule which aids / assists an enzyme
NAD and FAD in respiration both
gain hydrogen to form reduced
NAD and reduced FAD
NADP in photosynthesis gains
hydrogen to form reduced NADP

Question 6

Products of glycolysis

Answer 6

Net gain of 2 ATP
2 reduced NAD
2 pyruvate

Question 7

Location of link reaction

Answer 7

Mitochondrial matrix

Question 8

Link reaction

Answer 8

Reduced NAD and pyruvate are actively transported to matrix
pyruvate is oxidised to acetate (forming reduced NAD)
carbon removed and CO2 forms
acetate combines with coenzyme A to form acetylcoenzyme A (2C)

Question 9

Products of link reaction

Answer 9

2 acetylcoenzyme A molecules
2 carbon dioxide molecules released
2 reduced NAD molecules

Question 10

Location of krebs cycle

Answer 10

Mitochondrial matrix

Question 11

Krebs cycle

Answer 11

Acetylcoenzyme A combines with 4C molecule to produce a 6C molecule - enters cycle
oxidation-reduction reactions

Question 12

Products of Krebs cycle

Answer 12

8 reduced coenzymes:
6 reduced NAD
2 reduced FAD
2 ATP
4 carbon dioxide

Question 13

Location of oxidative phosphorylation

Answer 13

Cristae of mitochondria

Question 14

Mitochondria structure

Answer 14

Double membrane with inner membrane folded into cristae enzymes in matrix

Question 15

Role of reduced coenzyme in oxidative phosphorylation

Answer 15

Accumulate in mitochondrial matrix, where they release their protons and electrons
regenerate NAD and FAD to be used in glycolysis/ link reaction / Krebs cycle

Question 16

Role of electrons in oxidative phosphorylation

Answer 16

Electrons pass down series of
electron carrier proteins, losing energy as they move energy released actively transports H+ from
mitochondrial matrix to inter membrane space
electrochemical gradient
generated

Question 17

How is atp made in oxidative phosphorylation

Answer 17

Protons move down electrochemical gradient back into matrix via ATP synthase
ATP created movement of H+ is chemiosmosis