Key Area 2.2 Cell respiration

Question 1

What does respiration generate?

Answer 1

ATP

Question 2

What is ATP made of?

Answer 2

An adenine molecule with three phosphate groups attached.

Question 3

What is the first stage of aerobic respiration called?

Answer 3

Glycolysis.

Question 4

Where does glycolysis take place?

Answer 4

Cytoplasm.

Question 5

What is glucose broken down too?

Answer 5

Intermediates and finally pyruvate.

Question 6

What is part one of glycolysis called?

Answer 6

Energy investment stage.

Question 7

Why is step 1 called the energy investment stage?

Answer 7

Because 2 ATP are needed for the phosphorylation of intermediates.

Question 8

What is step 2 in glycolysis called?

Answer 8

Energy gain.

Question 9

Why is step 2 called the energy gain stage?

Answer 9

4 ATP are generated.

Question 10

Why is it said that there is a net gain of 2 ATP?

Answer 10

2 ATP are used but 4 are made so overall there is a gain of 2 ATP.

Question 11

What enzyme is used in glycolysis?

Answer 11

Dehydrogenase enzyme.

Question 12

What does the dehydrogenase enzyme do?

Answer 12

Removes hydrogen ions and electrons from intermediates.

Question 13

What picks up hydrogen ions and electrons in glycolysis?

Answer 13

NAD

Question 14

What does NAD turn into when it accepts hydrogen ions and electrons?

Answer 14

NADH

Question 15

Where does NADH carry the hydrogen ions and electrons to?

Answer 15

The electron transport chain.

Question 16

What is stage 2 of aerobic respiration called?

Answer 16

The citric acid cycle.

Question 17

What must be present for the citric acid cycle to start?

Answer 17

Oxygen.

Question 18

Where does the citric acid cycle take place?

Answer 18

Central matrix of the mitochondria.

Question 19

What is pyruvate broken down into?

Answer 19

An acetyl group.

Question 20

What does the acetyl group bind with? What does this form?

Answer 20

Coenzyme A. Acytyle Coenzyme A

Question 21

What is released from the ECS?

Answer 21

CO2 and Hydrogen.

Question 22

What does the acetyl from acetyl coenzyme A combine with? What does it form?

Answer 22

Oxaloacetate. Citrate

Question 23

What does hydrogen ions and electrons combine with? What does this form?

Answer 23

NAD to form NADH.

Question 24

How many ATP are produced from the citric acid cycle?

Answer 24

1

Question 25

What happens to oxaloacetate?

Answer 25

It is regenerated for continuation of the cycle.

Question 26

What is stage 3 of aerobic respiration called?

Answer 26

The electron transport chain (ECS).

Question 27

Where does ECS take place?

Answer 27

Inner membrane of the mitochondria.

Question 28

What does the NADH do?

Answer 28

Passes electrons to the electron transport system.

Question 29

What do the electrons then do?

Answer 29

Flow along the electron transport system and release energy.

Question 30

What is this energy used for?

Answer 30

To pump hydrogen ions across the mitochondrial membrane and into the inner membrane.

Question 31

What does hydrogen move through?

Answer 31

ATP synthase.

Question 32

What does ATP synthase do?

Answer 32

Makes ATP.

Question 33

What is oxygen?

Answer 33

The final hydrogen ion and electron acceptor.

Question 34

What does the oxygen form when it accepts the hydrogen ions and electrons?

Answer 34

Water.

Question 35

What is fermentation?

Answer 35

Respiration which takes place in the absence of oxygen.

Question 36

When does fermentation occur in animals?

Answer 36

During strenuous exercise.

Question 37

What is pyruvate converted into during fermentation in animals?

Answer 37

Lactate.

Question 38

Is fermentation in animals reversible?

Answer 38

Yes.

Question 39

Is fermentation is plants reversible?

Answer 39

No.

Question 40

Why is fermentation is plants irreversible?

Answer 40

The cells become damaged due to the products of fermentation.

Question 41

What are the products of fermentation in plants?

Answer 41

Ethanol and CO2