Cellular Respiration

Question 1

What is cellular respiration?

Answer 1

A series of metabolic pathways that release energy from food.

Question 2

What does cellular respiration regenerate?

Answer 2

ATP - Adenosine Triphosphate.

Question 3

What is ATP composed of?

Answer 3

One adenosine and three inorganic phosphates (Pi).

Adenosine - Pi - Pi - Pi

Question 4

How is the energy released from ATP?

Answer 4

When the final bond breaks.

Question 5

What happens when ATP’s bonds are broken?

Answer 5

Left with ADP - Adenosine Diphosphate.

Adenosine - Pi - Pi + Pi

Question 6

What is glycolysis?

Answer 6

The breakdown of glucose to pyruvate in the cytoplasm.

Question 7

Where does glycolysis take place?

Answer 7

In the cytoplasm

Question 8

What is ATP required for during the energy investment stage of glycolysis?

Answer 8

For the phosphorylation of glucose and intermediates.

Question 9

When does fermentation take place?

Answer 9

In the absence of oxygen.

Question 10

What happens during fermentation in animal cells?

Answer 10

Pyruvate is converted to lactate in a reversible reaction.

Question 11

What happens during fermentation in plants and yeast?

Answer 11

Ethanol and CO2 are produced in an irreversible reaction.

Question 12

Compare ATP between fermentation and aerobic respiration.

Answer 12

Fermentation results in much less ATP being produced than aerobic respiration.

Question 13

What is phosphorylation?

Answer 13

An enzyme-controlled process where a phosphate group is added to a molecule.

Question 14

What are the three stages of cellular respiration?

Answer 14

1. glycolysis
2. citric acid cycle
3. electron transport chain

Question 15

Where does glycolysis take place?

Answer 15

Cytoplasm

Question 16

Where does the citric acid cycle take place?

Answer 16

Matrix of the mitochondria

Question 17

Where does the electron transport chain take place?

Answer 17

Inner mitochondrial membrane

Question 18

What is glycolysis?

Answer 18

The breakdown of glucose into pyruvate.

Glucose > intermediate products > Pyruvate.

Question 19

Is oxygen required for glycolysis?

Answer 19

No

Question 20

What is required for converting glucose to intermediate products and what is this stage called?

Answer 20

2 ATP are required in the energy investment stage.

Question 21

What happens when the intermediate products are formed into pyruvate?

Answer 21

There is a net gain of 2 ATP - called the energy pay-off stage.

Question 22

What removed hydrogen ions and electrons from the pyruvate molecules?

Answer 22

Dehydrogenase enzymes

Question 23

Where do hydrogen ions and electrons get passed?

Answer 23

To the coenzyme NAD to form NADH.

Question 24

Does the citric acid cycle require oxygen?

Answer 24

Yes

Question 25

What is a series of dehydrogenase enzyme-controlled reactions resulting in the generation of ATP and release of CO2 and H2?

Answer 25

The citric acid cycle.

Question 26

What is the first step of the citric acid cycle?

Answer 26

Pyruvate is converted to acetyl. Acetyl combines with coenzyme A to form acetyl coenzyme A.

Question 27

What is the second step of the citric acid cycle?

Answer 27

Acetyl coenzyme A combines with oxaloacetate to form citrate which reacts with CO2 to form oxaloacetate and then all over again.

Question 28

Where are the hydrogen ions and electrons passed on from the citric acid cycle?

Answer 28

To the electron transport chain.

Question 29

Does the electron transport chain require oxygen?

Answer 29

Yes

Question 30

What happens in the electron transport chain?

Answer 30

Oxygen, hydrogen ions and electrons form NADH to generate ATP and form water.

Question 31

What is the electron transport chain?

Answer 31

A series of carrier proteins attached to the inner mitochondrial membrane.

Question 32

How is the ATP generated in the electron transport chain?

Answer 32

Hydrogen ions flow through the ATP synthase protein back through the inner membrane generating 36 ATP.