KA7 - Cellular Respiration

Question 1

What is respiration?

Answer 1

Respiration is the process by which energy is released from food. It occurs in all living cells

Question 2

What is the main substrate writhing the respiration pathway?

Answer 2

Glucose

Question 3

What three parts can the metabolic pathway involved in respiration be split into?

Answer 3

Glycolysis

Citric acid cycle

The electron transport chain

Question 4

What is phosphorylation?

Answer 4

Phosphorylation is an enzyme controlled process by which a phosphate group is added to a molecule

Question 5

Give an example of phosphorylation?

Answer 5

When low energy ADP and Pi combine to form high energy ATP

Question 6

Where does glycolysis take place?

Answer 6

Cytoplasm

Question 7

Does glycolysis require energy?

Answer 7

No

Question 8

What is glycolysis?

Answer 8

Glycolysis involves the breakdown of glucose into two pyruvate molecules

Question 9

What are the two phases involved in glycolysis?

Answer 9

An energy investment phase

An energy payoff phase

Question 10

What happens to pyruvate in aerobic conditions?

Answer 10

In aerobic conditions, pyruvate is broken down into an acetyl group.

Question 11

What does the acetyl group do?

Answer 11

The acetyl group then combines with coenzyme A to form acetyl coenzyme A

Question 12

What is the stage after glycolysis?

Answer 12

The citric acid cycle

Question 13

When does the citric acid cycle take place?

Answer 13

Only if oxygen is present

Question 14

Where does the citric acid cycle take place?

Answer 14

The matrix of the mitochondria

Question 15

What is the citric acid cycle controlled by?

Answer 15

Enzymes including dehydrogenase

Question 16

What is the first stage of the citric acid cycle?

Answer 16

In the citric acid cycle, the acetyl group from acetyl coenzyme A combines with oxaloacetate to form citrate

Question 17

What is the second stage of the citric acid cycle?

Answer 17

During a series of enzyme controlled steps, citrate is gradually converted back into oxaloacetate which results in the generation of ATP and release of carbon dioxide

Question 18

What is the third stage of the citric acid cycle?

Answer 18

Dehydrogenase enzymes also remove hydrogen ions and electrons and pass them to the coenzyme NAD, forming NADH

Question 19

What is the final stage of the citric acid cycle?

Answer 19

The hydrogen ions and electrons from NADH are passed to the electron transport chain

Question 20

What is the last stage of respiration?

Answer 20

The electron transport chain

Question 21

Does the electron transport chain require oxygen?

Answer 21

Yes

Question 22

Where does the electron transport chain take place?

Answer 22

The inner mitochondrial membrane

Question 23

Where is the majority of ATP made?

Answer 23

The electron transport chain(stage 3)

Question 24

How is the majority of ATP made during the electron transport chain?

Answer 24

This is done using the energy from the electrons which have been removed during glycolysis and the citric acid cycle

Question 25

What is the first stage of the electron transport chain?

Answer 25

Electrons are passed along the electron transport chain releasing energy

Question 26

What is the second stage of the electron transport chain?

Answer 26

This energy allows hydrogen ions to be pumped across the inner mitochondrial membrane

Question 27

What is the third stage of the electron transport chain?

Answer 27

These hydrogen ions then flow back through the membrane protein ATP synthase (an enzyme) which results in the production of ATP

Question 28

What is the final stage of the electron transport chain?

Answer 28

Finally, the hydrogen ions and electrons combine with oxygen to form water

Oxygen is the final hydrogen acceptor of the electron transport chain

Question 29

What is the role of ATP in the transfer of energy?

Answer 29

ATP is used to transfer energy to cellular processes which require energy

Question 30

Give 4 example of cellular processes which require energy?

Answer 30

Muscle cell contraction

Transmission of nerve impulses

Cell division

Protein synthesis