Cellular respiration

Question 1

What are the products of aerobic respiration?

Answer 1

Carbon dioxide, water, ATP

Question 2

What is the name for the first stage of respiration?

Answer 2

Glycolysis

Question 3

Where does glycolysis take place?

Answer 3

Cytoplasm

Question 4

What is the name for the second stage of respiration?

Answer 4

Citric acid cycle

Question 5

Where does the citric acid cycle occur?

Answer 5

Matrix of mitochondria

Question 6

What happens in glycolysis?

Answer 6

Glucose -> Pyruvate
2 ATP used, 4 ATP produced, Net Gain 2 ATP
NADH produced

Question 7

Which enzyme removes hydrogen ions and electrons during respiration?

Answer 7

Dehydrogenase

Question 8

Which co-enzymes carry hydrogen and high-energy electrons to the electron transport chain?

Answer 8

NAD / FAD

Question 9

What is meant by a “net gain” of 2 ATP during glycolysis?

Answer 9

2 ATP are used, 4 ATP are produced

Question 10

What happens during the citric acid cycle?

Answer 10

Pyruvate converted to Acetyl Co A which combines with oxaloacetate to form citrate. Produces NADH, FAD, CO2 and some ATP.

Question 11

Which stage in aerobic respiration can result in both NADH and FADH2 being produced?

Answer 11

Citric Acid Cycle

Question 12

What happens during the electron transport chain?

Answer 12

Electrons provide energy to pump H ions into intermembrane space. Hydrogen ions return to cytoplasm through ATP synthase which results in ATP being made.

Question 13

Where are electron transport chains for aerobic respiration found?

Answer 13

The inner membrane of the mitochondria

Question 14

Why are the electrons required in the electron transport chain?

Answer 14

Provide the energy for the electron transport chain to pump H ions into intermembrane space.

Question 15

Which enzyme is responsible for synthesising ATP from ADP + Pi?

Answer 15

ATP Synthase

Question 16

What drives the synthesis of ATP by ATP Synthase?

Answer 16

The return flow of hydrogen ions.

Question 17

What is the role of oxygen in the electron transport chain?

Answer 17

Acts as the final acceptor of H ions and electrons, combining with them to form water.

Question 18

What happens during the energy investment phase of glycolysis?

Answer 18

ATP are used to phosphorylate intermediates.

Question 19

What happens during the energy pay-off phase of glycolysis.

Answer 19

ATP are produced.

Question 20

What happens to the pyruvate after glycolysis?

Answer 20

Converted into an acetyl group and combines with co-enzyme A to make acetyl co-A.

Question 21

What happens to acetyl co A during the citric acid cycle?

Answer 21

It combines with oxaloacetate to make citrate.

Question 22

What is produced during the citric acid cycle?

Answer 22

CO2, ATP, NADH, FADH2

Question 23

What happens to pyruvate in the absence of oxygen?

Answer 23

Undergoes fermentation to form lactate in animals or ethanol and CO2 in plants.

Question 24

What happens to the NADH and FAD generated in glycolysis and the citric acid cycle?

Answer 24

They pass the hydrogen ions and electrons to the electron transport chain.

Question 25

Name two alternative respiratory substrates?

Answer 25

Fats, proteins

Question 26

Which alternative respiratory substrate would only be used after periods of prolonged starvation.

Answer 26

Proteins

Question 27

What are the subunits of fats?

Answer 27

Glycogen and glycerol

Question 28

What are the smallest subunits of carbohydrates?

Answer 28

Glucose