Respiration

Question 1

Definition: RESPIRATION

Answer 1

• series of cellular processes that involves the breakdown of organic compounds, in the presence of enzymes, to release energy for other cellular processes

Question 2

Removal of terminal phosphate group of ATP yields how much energy?

Answer 2

30.6 kJ mol-1

Question 3

Processes in cellular respiration that produce ATP

Answer 3

• substrate level phosphorylation

- oxidative phosphorylation

Question 4

Stages of AEROBIC RESPIRATION

Answer 4

1. Glycolysis
2. Link Reaction
3. Krebs Cycle
4. Oxidative phosphorylation

Question 5

Location of GLYCOLYSIS

Answer 5

Cytosol

Question 6

Location of LINK REACTION

Answer 6

Mitochondrial matrix

Question 7

Location of KREBS CYCLE

Answer 7

Mitochondrial matrix

Question 8

Location of OXIDATIVE PHOSPHORYLATION

Answer 8

Inner mitochondrial membrane

Question 9

Outline of GLYCOLYSIS

Answer 9

• 1 molecule of glucose (6C) partially oxidised and broken down into 2 molecules of pyruvate (3C)
• reduces 2 molecules of NAD to NADH
• 2 ATPs produced by SLP

Question 10

Outline of LINK REACTION

Answer 10

• transport protein embedded in inner mitochondrial membrane transfers pyruvate from cytosol to mitochondrila matrix by active transport
• pyruvates converted into acetyl CoA; each pyruvate loses a CO2 molecule through decarboxylation
• remaining 2C fragment undergoes oxidation by dehydrogenation, reducing 2 NAD to NADH
• Coenzyme A added, producing acetyl CoA
• process of oxidative decarboxylation catalysed by pyruvate dehydrogenase; produces 2 ATPs by SLP

Question 11

Outline of KREBS CYCLE

Answer 11

• each acetyl CoA oxidised and broken down into 2 molecules of CO2 each
• 6 NAD and 2 FAD reduced to NADH and FADH2 respectively
• 2 ATPs produced by SLP

Question 12

Outline of OXIDATIVE PHOSPHORYLATION

Answer 12

• waiting

Question 13

Major phases of Glycolysis

Answer 13

1. Energy-investment phase (ATP utilised)

2. Energy-payoff phase (ATP formed)

Question 14

Roles of NAD+ and FAD in aerobic respiration

Answer 14

• NAD is a coenzyme for dehydrogenase; FAD is a prosthetic group for dehydrogenases
• electrons lose little energy when transferred from glucose to NAD+ in glycolysis; NADH formed contains stored energy
• NAD+ and FAD act as mobile e carriers, carrying these e to the ETC
• e get passed down; releases energy used to drive OP, producing ATP by chemiosmosis
• 2.5 ATP from NADH & 1.5 ATP from FADH2
• after passing e to ETC, NADH and FADH get reoxidised back into NAD+ and FAD+; oxidation in glycolysis can proceed