Chapter 9: Cellular Respiration

Question 1

What is cellular respiration?

Answer 1

Is a metabolic pathway that breaks down glucose (sugar) and produces ATP

Question 2

What are the steps of cellular respiration?

Answer 2

Glycolysis (within cytoplasm)
Pyruvate oxidation (within mitochondria)
The Citric Acid Cycle/Kreb’s Cycle (within mitochondria)
Oxidative phosphorylation (within mitochondria)

Question 3

What is glycolysis?

Answer 3

Is a cytoplasmic pathway which breaks down glucose into two three-carbon compounds and generate energy; is an anaerobic process; requires a bit of energy itself

Question 4

What are the products of glycolysis?

Answer 4

2 ATP molecules
2 NADH molecules
2 pyruvic acid molecules/pyruvates

Question 5

What is pyruvate oxidation?

Answer 5

Is the conversion of one pyruvate into one acetyl-CoA; an aerobic process

Question 6

What are the products of pyruvate oxidation?

Answer 6

2 carbon dioxide molecules
2 NADH molecules
2 Acetyl-CoA molecules

Question 7

What is the Citric Acid Cycle/Kreb’s Cycle?

Answer 7

Is a series of chemical reaction to release stored energy; an aerobic process

Question 8

What are the products of the Kreb’s Cycle?

Answer 8

4 carbon dioxide molecules
6 NADH molecules
2 FADH2 molecules
2 ATP

Question 9

Where do both pyruvate oxidation and the Kreb’s Cycle occur?

Answer 9

Within the mitochondrial matrix, the space inside the mitochondria’s inner membrane

Question 10

List the totality of all the products from all processes until the electron transport chain.

Answer 10

4 ATP
10 NADH molecules
2 FADH2 molecules
6 released carbon dioxide molecules

Question 11

What are NADH and FADH2?

Answer 11

Coenzymes that help transport electrons and will be useful in creating more ATP later on

Question 12

Describe the structure of the mitochondria.

Answer 12

Refer to diagram in notebook

Question 13

Why does the mitochondria have DNA?

Answer 13

It is theorized that mitochondria were initially unicellular organisms (prokaryotes, bacteria) that entered a eukaryotic cell and developed a mutually beneficial relationship with it, with the cell providing the mitochondria protection and the mitochondria providing energy (ATP).

Question 14

What is oxidative phosphorylation?

Answer 14

The process in which ATP is formed as a result of the transfer of electrons from NADH and FADH2 to O2 by a series of electrons carriers; takes place in the mitochondria and is a major source of ATP in aerobic organisms

Question 15

What are the products of oxidative phosphorylation?

Answer 15

26-28 ATP molecules

Water

Question 16

How many ATP are formed in cellular respiration in total (the maximum)?

Answer 16

30-32 ATP for one glucose molecule

Question 17

What type of osmosis do the hydrogen ions (protons) conduct to reach the intermembrane space?

Answer 17

Active transport (coming from a low concentration gradient to a high one; requires cellular energy)

Question 18

What type of osmosis (chemiosmosis) do hydrogen ions (protons) use to reach the matrix?

Answer 18

Facilitated diffusion (through ATP synthase)

Question 19

How is ATP produced in chemiosmosis?

Answer 19

The protons in the intermembrane space have a natural tendency to go to a region of lower concentration gradient, but because they are ions, they require the passage through a channel protein called ATP synthase. The protons power ATP synthase to phosphorylize ADP, giving the energy required to merge ADP and a phosphate group.

Question 20

How is ATP produced in chemiosmosis?

Answer 20

The proton gradient formed by the propulsion of hydrogen ions across the inner membrane creates a need for those ions to pass through the membrane in accordance to facilitated diffusion (from a region of high concentration to lower concentration). In passing through ATP synthase, the protons power the protein to phosphorylize ADP; in other words, the protons provide the energy for the synthesis of ATP.

Question 21

What is the electron transport chain?

Answer 21

The passage of electrons, which were lost in the conversion from NADH to NAD+ and FADH2 to FAD, through a series of protein complexes. Oxygen is the final acceptor of these electrons, which creates water.

Question 22

How many protons are lost in the conversion of FADH2 to FAD?

Answer 22

Two hydrogen ions/atoms

Question 23

Name the requirements for ATP.

Answer 23

• ADP
• a phosphate group
• energy

Question 24

What is chemiosmosis?

Answer 24

(In general) the process of the facilitated diffusion of ions, particularly H+, across a selectively permeable membrane