7.1 Bio content

Question 1

What is cellular respiration?

Answer 1

The process by which cells extract energy from food molecules to generate ATP.

Question 2

What are the four stages of cellular respiration (in order)?

Answer 2

1) Glycolysis, 2) Pyruvate processing, 3) Citric acid cycle, 4) Electron transport and oxidative phosphorylation.

Question 3

What is the overall chemical equation for cellular respiration?

Answer 3

C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + ~36 ATP.

Question 4

Where does cellular respiration occur in eukaryotes?

Answer 4

Cytoplasm (glycolysis) and mitochondria (remaining steps).

Question 5

What is a redox reaction?

Answer 5

A reaction where electrons are transferred between molecules.

Question 6

What is oxidation?

Answer 6

The loss of electrons.

Question 7

What is reduction?

Answer 7

The gain of electrons.

Question 8

What is NAD+?

Answer 8

An electron carrier that accepts electrons to become NADH.

Question 9

What are two main electron carriers in cellular respiration?

Answer 9

NAD+/NADH and FAD/FADH2.

Question 10

What does ATP stand for?

Answer 10

Adenosine triphosphate.

Question 11

What happens during ATP hydrolysis?

Answer 11

ATP → ADP + Pi (exergonic reaction that releases energy).

Question 12

What is phosphorylation?

Answer 12

Adding a phosphate group to a molecule.

Question 13

What are the two types of phosphorylation that generate ATP?

Answer 13

Substrate-level phosphorylation and oxidative phosphorylation.

Question 14

Where does glycolysis occur?

Answer 14

In the cytoplasm.

Question 15

Is oxygen required for glycolysis?

Answer 15

No, glycolysis is anaerobic.

Question 16

What are the inputs of glycolysis?

Answer 16

1 glucose, 2 NAD+, 2 ATP, 4 ADP.

Question 17

What are the outputs of glycolysis?

Answer 17

2 pyruvate, 2 NADH, 4 ATP (net gain of 2 ATP).

Question 18

What are the two phases of glycolysis?

Answer 18

Energy investment phase and energy payoff phase.

Question 19

Where does pyruvate processing occur in eukaryotes?

Answer 19

Mitochondrial matrix.

Question 20

What happens to pyruvate during this step?

Answer 20

One carbon is released as CO2, NADH is produced, and acetyl CoA is formed.

Question 21

What enzyme complex catalyzes pyruvate oxidation?

Answer 21

Pyruvate dehydrogenase.

Question 22

Where does the citric acid cycle occur?

Answer 22

In the mitochondrial matrix.

Question 23

What molecule enters the citric acid cycle?

Answer 23

Acetyl CoA.

Question 24

What are the outputs per turn of the cycle?

Answer 24

3 NADH, 1 FADH2, 1 ATP (or GTP), and 2 CO2.

Question 25

How many turns of the cycle occur per glucose molecule?

Answer 25

Two turns.

Question 26

What is regenerated at the end of each cycle?

Answer 26

Oxaloacetate.

Question 27

Where is the electron transport chain located?

Answer 27

Inner mitochondrial membrane.

Question 28

What do NADH and FADH2 donate to the ETC?

Answer 28

High-energy electrons.

Question 29

What is the final electron acceptor in the ETC?

Answer 29

Oxygen (O2).

Question 30

What is produced when electrons combine with O2?

Answer 30

Water (H2O).

Question 31

How is ATP produced in the ETC?

Answer 31

Through chemiosmosis and ATP synthase, driven by a proton (H+) gradient.

Question 32

How many ATP are generated from one glucose molecule (approx.)?

Answer 32

About 36 ATP.

Question 33

What is the total yield from glucose oxidation?

Answer 33

6 CO2, 10 NADH, 2 FADH2, and 4 ATP.

Question 34

What are catabolic pathways?

Answer 34

Pathways that break down molecules to release energy (e.g., respiration).

Question 35

What are anabolic pathways?

Answer 35

Pathways that build complex molecules using energy (e.g., biosynthesis).

Question 36

How are fats used in cellular respiration?

Answer 36

Glycerol enters glycolysis; fatty acids are converted to acetyl CoA.

Question 37

How are proteins used in cellular respiration?

Answer 37

Amino acids are deaminated and converted into intermediates of glycolysis or the citric acid cycle.

Question 38

What is feedback inhibition?

Answer 38

A process where the end product of a pathway inhibits an enzyme involved earlier in the pathway.

Question 39

What does homeostasis mean?

Answer 39

Maintaining a stable internal environment despite external changes.