Membranes, Enzymes and Respiration Study Guide

Question 1

What is the equation for cellular respiration?

Answer 1

C6H12O6 + 6 O2 –> 6 CO2 + 6 H2O + ATP

Question 2

What type of reaction is cellular respiration?

Answer 2

The overall reaction of cellular respiration is a REDOX reaction.

Question 3

How do you know if a molecule is reduced?

Answer 3

A molecule is reduced when it gains electrons and energy, as electrons carry energy.

Question 4

What happens to NAD+ in cellular respiration?

Answer 4

NAD+ is reduced to NADH by gaining electrons and hydrogen.

Question 5

How do you know if a molecule is oxidized?

Answer 5

A molecule is oxidized when it loses electrons, gaining oxygen atoms or losing hydrogen atoms.

Question 6

What reaction happens in the cytoplasm?

Answer 6

Glycolysis, the breakdown of glucose into pyruvate, occurs in the cytoplasm.

Question 7

What are the products of glycolysis?

Answer 7

Glycolysis produces pyruvate, ATP, and NADH.

Question 8

What happens to pyruvate in yeast when there is no oxygen?

Answer 8

Pyruvate is converted into ethanol and carbon dioxide through fermentation.

Question 9

What happens to pyruvate in animals if no oxygen is present?

Answer 9

Pyruvate is converted into lactic acid through lactic acid fermentation.

Question 10

What is the purpose of making and using NADH in fermentation?

Answer 10

To regenerate NAD+ so glycolysis can keep producing ATP.

Question 11

Give examples of foods that use bacteria or yeast to digest sugar anaerobically.

Answer 11

Examples include bread, yogurt, and kefir.

Question 12

What is the general structure of the mitochondria?

Answer 12

The mitochondria has two membranes: an outer membrane and an inner membrane. The space inside the inner membrane is called the matrix, and the area between the membranes is the intermembrane space.

Question 13

What is the waste product when pyruvate is oxidized to acetyl-CoA?

Answer 13

The waste product is carbon dioxide (CO₂).

Question 14

What molecule carries the hydrogen/electron released from pyruvate?

Answer 14

NADH carries the hydrogen/electrons released from pyruvate.

Question 15

Where does acetyl-CoA go to get further oxidized?

Answer 15

Acetyl-CoA enters the Krebs cycle in the mitochondria.

Question 16

Why is the Krebs cycle considered a circular enzyme pathway?

Answer 16

It regenerates its starting molecule oxaloacetate at the end.

Question 17

What are the products of the Krebs cycle?

Answer 17

The products are NADH and FADH2 (electron carriers), ATP (a high-energy molecule), and CO2 (a waste product).

Question 18

Where do NADHs drop off their electrons?

Answer 18

NADH drops off its electrons at the electron transport chain.

Question 19

What do the molecules in the inner membrane do with the energy from electrons?

Answer 19

They pump protons from the matrix into the intermembrane space, creating a proton gradient.

Question 20

What metal is used in the electron transport chain?

Answer 20

Iron is used to redox the electrons along from one complex to the next.

Question 21

What do complexes 1, 3, and 4 pump across the membrane?

Answer 21

They pump hydrogen ions across the membrane.

Question 22

Why is oxygen used in cellular respiration?

Answer 22

Oxygen is the final electron acceptor in the electron transport chain, where it gets reduced to water (H2O).

Question 23

What enzyme is responsible for ATP mass production?

Answer 23

The enzyme is ATP synthase.

Question 24

How many ATPs are produced per glucose molecule?

Answer 24

30-32 ATP are produced per glucose molecule.

Question 25

What does the oxygen you breathe in get turned into?

Answer 25

It combines with hydrogen to form water (H2O).

Question 26

What is the source of the CO2 you exhale?

Answer 26

The source of carbon dioxide is the byproduct of cellular respiration.