Chapter 6

Question 1

What is the overall equation for aerobic cellular respiration?

Answer 1

C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + 30–32 ATP

Question 2

How is aerobic respiration related to photosynthesis?

Answer 2

They recycle each other’s outputs as inputs.

Question 3

Why is aerobic respiration important?

Answer 3

Cells need a constant supply of energy (ATP) to function.

Question 4

What organelle is key for aerobic respiration stages 2 and 3?

Answer 4

Mitochondria

Question 5

What is the space inside the inner mitochondrial membrane called?

Answer 5

Mitochondrial matrix

Question 6

What are cristae in mitochondria?

Answer 6

Folds in the inner mitochondrial membrane.

Question 7

Where does glycolysis occur?

Answer 7

Cytosol

Question 8

Does glycolysis require oxygen?

Answer 8

No

Question 9

What are the outputs of glycolysis?

Answer 9

2 pyruvate, 2 ATP, 2 NADH

Question 10

Where does the Krebs cycle occur?

Answer 10

Mitochondrial matrix

Question 11

What is pyruvate converted into before entering the Krebs cycle?

Answer 11

Acetyl-CoA

Question 12

How much ATP does the Krebs cycle produce?

Answer 12

2 ATP

Question 13

Where does the Electron Transport Chain occur?

Answer 13

Cristae (inner mitochondrial membrane)

Question 14

What molecule accepts electrons and protons to form water in ETC?

Answer 14

Oxygen

Question 15

What is the role of ATP synthase?

Answer 15

Allows protons to flow into the matrix, generating ATP.

Question 16

How much ATP does the ETC generate?

Answer 16

26–28 ATP

Question 17

What are the outputs of the Krebs cycle?

Answer 17

4 CO₂, 2 ATP, 6 NADH, 2 FADH₂

Question 18

What are the outputs of ETC?

Answer 18

6 H₂O, 26–28 ATP, 10 NAD⁺, 2 FAD

Question 19

What are the unloaded coenzymes in respiration?

Answer 19

ADP, FAD, NAD⁺, NADP⁺

Question 20

What are the loaded coenzymes in respiration?

Answer 20

ATP, FADH₂, NADH, NADPH

Question 21

Where does anaerobic fermentation occur?

Answer 21

Cytosol

Question 22

What is the purpose of fermentation?

Answer 22

Replenishes NAD⁺

Question 23

What are the products of lactic acid fermentation?

Answer 23

2 lactic acid + 2 ATP

Question 24

What happens to lactic acid when oxygen is available?

Answer 24

Converted back into pyruvate

Question 25

What are the products of ethanol fermentation?

Answer 25

2 ethanol + 2 CO₂ + 2 ATP

Question 26

What stages does aerobic respiration include?

Answer 26

Glycolysis, Krebs cycle, Electron Transport Chain

Question 27

What stages does anaerobic respiration include?

Answer 27

Glycolysis, Lactic Acid or Ethanol Fermentation

Question 28

Where does aerobic respiration take place?

Answer 28

Cytosol + mitochondria

Question 29

Where does anaerobic respiration take place?

Answer 29

Cytosol

Question 30

What are the inputs of aerobic respiration?

Answer 30

Glucose + oxygen

Question 31

What are the outputs of aerobic respiration?

Answer 31

Carbon dioxide + H₂O

Question 32

What are the outputs of anaerobic respiration?

Answer 32

Lactic acid, ethanol, CO₂

Question 33

How many ATP does aerobic respiration yield?

Answer 33

30–32 ATP

Question 34

How many ATP does anaerobic respiration yield?

Answer 34

2 ATP

Question 35

Is aerobic respiration fast or slow?

Answer 35

Slow

Question 36

Is anaerobic respiration fast or slow?

Answer 36

Fast

Question 37

Is aerobic respiration sustainable long-term?

Answer 37

Yes

Question 38

Is anaerobic respiration sustainable long-term?

Answer 38

No, due to toxicity

Question 39

What is the main factor affecting respiration rate?

Answer 39

ATP demand

Question 40

What is the optimal temperature for human cellular respiration?

Answer 40

36.7°C

Question 41

What is the optimal pH of cytoplasm?

Answer 41

7.2

Question 42

What is the optimal pH of the mitochondrial matrix?

Answer 42

7.8

Question 43

How does glucose availability affect respiration rate?

Answer 43

Higher glucose increases rate until it plateaus.

Question 44

How does oxygen availability affect respiration rate?

Answer 44

Less oxygen = lower rate; may switch to anaerobic fermentation.

Question 45

What other molecules besides glucose can be used for respiration?

Answer 45

Lipids and proteins (glucose preferred).

Question 46

How do enzyme inhibitors affect respiration?

Answer 46

They slow it down by reducing enzyme activity.

Question 47

Why can enzyme inhibition be beneficial?

Answer 47

Helps regulate respiration (e.g., via reversible allosteric inhibition).

Question 48

What are biofuels made from?

Answer 48

Biomass (organic material)

Question 49

Why are biofuels considered carbon neutral?

Answer 49

No net CO₂ is added to the atmosphere.

Question 50

What is the first step in making bioethanol?

Answer 50

Deconstruction – breaking down biomass to increase surface area.

Question 51

What enzyme breaks down starch and cellulose in biofuel production?

Answer 51

Amylase

Question 52

What does fermentation produce in bioethanol production?

Answer 52

Ethanol (via yeast)

Question 53

What happens after ethanol is produced in fermentation?

Answer 53

It is purified and dehydrated to form usable biofuel.

Question 54

What is bioethanol made from?

Answer 54

Plant sugars

Question 55

What is biodiesel made from?

Answer 55

Fatty acids (e.g., vegetable oils, animal fats)

Question 56

List one advantage of biofuels.

Answer 56

Reduce climate emissions

Question 57

List one disadvantage of biofuels.

Answer 57

May conflict with food production (food vs fuel)

Question 58

How do biofuels enhance energy security?

Answer 58

Reduce reliance on fossil fuels and allow local production

Question 59

What is a second-order environmental impact of biofuels?

Answer 59

May affect genetic diversity or emit nitrous oxide