Cellular Respiration

Question 1

What kind of process is cellular respiration?

Answer 1

Exergonic

Question 2

What kind of process is photosynthesis?

Answer 2

Endergonic

Question 3

Aerobic Respiration

Answer 3

consumes oxygen as a reactant

Question 4

Anaerobic respiration

Answer 4

replaces oxygen with another inorganic molecule

Question 5

General formula of cellular respiration

Answer 5

C6H12O6 + 6O2 -> 6CO2 + 6H2O + ATP

Question 6

Oxidation

Answer 6

The loss of electrons

Question 7

Reduction

Answer 7

The gain of electrons

Question 8

Reducing agent

Answer 8

Electron donor

Question 9

Oxidizing agent

Answer 9

Electron acceptor

Question 10

Electron carrier used in cellular respiration

Answer 10

NAD+, NADH

Question 11

Dehydrogenases

Answer 11

• Enzymes that transfer 2 electrons and a proton from an organic compound to NAD+
• This produces NADH

Question 12

Substrate-level phosphorylation

Answer 12

• Process by which a phosphate is attached to an organic molecule is passed onto another molecule without the use of an electron transport chain
• Formation of ATP

Question 13

Glycolysis

Answer 13

• Breakdown of glucose into 2 pyruvate molecules
• Takes place in the cytoplasm (no oxygen)

Question 14

Two major phases of glycolysis

Answer 14

• Energy investment phase
• Energy payoff phase

Question 15

Glycolysis general formula

Answer 15

Glucose + 2NAD+ + 2ADP + 2phosphates -> 2ATP + 2NADH + 2H+ +2H2O + 2pyruvate

Question 16

Pyruvate oxidation

Answer 16

• Begin with pyruvate (3 carbons) which undergoes changes to become acetyl (2 carbons)
  1. Decarboxylation (-CO2)
  2. Oxidation by NAD+
  3. Co-enzyme A attaches to acetyl

Question 17

Pyruvate oxidation formula per 1 pyruvate

Answer 17

pyruvate + NAD+ + CoA -> NADH + H+ + CO2 + acetyl-CoA

Question 18

Pyruvate oxidation formula per glucose

Answer 18

2pyruvate + 2NAD+ + 2CoA -> 2NADH + 2H+ + 2CO2 + 2acetyl-CoA

Question 19

What step does the kerb’s cycle start and end with?

Answer 19

oxaloacetate

Question 20

Kreb’s Cycle

Answer 20

• Oxaloacetate (4 carbons) attaches to acetyl (2 carbons) this triggers the beginning of the Kreb’s Cycle
• 2 cycles per glucose
• By the end of the cycle all carbons from glucose are oxidized and have been removed as CO2

Question 21

Kreb’s cycle formula per acetyl-CoA

Answer 21

acetyl-CoA + 3NAD+ + FAD + ADP + phosphate + H2O -> ATP + FADH2 +3NADH + H+ + 2CO2 + CoA

Question 22

Kreb’s cycle formula per glucose

Answer 22

2acetyl-CoA + 6NAD+ +2FAD +2ADP + 2phosphate + 2H2O -> 2ATP + 2FADH2 + 6NADH + 2H+ + 4CO2 + 2CoA

Question 23

Oxidative phosphorylation

Answer 23

The synthesis of ATP through the energy released by the transfer of electrons using an electron transport chain and chemiosmosis

Question 24

Electron Transport Chain

Answer 24

• Involves several membrane bound proteins and active molecules
• Pumps 3H+’s per NADH
• Pumps 2H+’s per FADH2

Question 25

What starts the electron transport chain?

Answer 25

- NADH + H+ gets oxidized to NAD+

Question 26

What is O2 in the ETC

Answer 26

- "ultimate electron acceptor" - because of it's high electronegativity

Question 27

What is H2O in the ETC?

Answer 27

The last molecule that contains glucose's electrons

Question 28

Chemiosmosis

Answer 28

- Creates an electrochemical or proton gradient which motivates H+ to re-enter the matrix through ATP synthase - The electrochemical gradient creates a "proton motive force" which moves H+ ions

Question 29

How does chemiosmosis work?

Answer 29

- H+ ions are pumped through ATP Synthase - Causes ADP + Pi to react and form ATP - 4 protons per 1 ATP molecule

Question 30

How much ATP is made from cellular respiration?

Answer 30

30 or 32 ATP depending on which NADH shunt is used

Question 31

Phosphofructokinase

Answer 31

Enzyme in glycolysis that regulates the rate at which glucose is broken down