Respiration

Question 1

Glycolysis

Answer 1

1 Glucose phosphorylated into 1 glucose phosphate, using 1 ATP. GP phosphorylated to unstable 6C compound, splits to for 2 triose phosphates. 2 NAD molecules reduced triose phosphates lose 1 H+ each, 4 ATP synthesised. Forms 2 pyruvate, net 2 ATP, 2 NADH.

Question 2

Anaerobic respiration, alcoholic fermentation

Answer 2

Pyruvate releases CO2 (decarboxylated), forms ethanal, NADPH oxidised to form ethanol.

Question 3

Anaerobic respiration, lactate fermentation

Answer 3

Pyruvate reduced to lactate, NAD regenerated to continue glycolysis to produce 2 ATP

Question 4

Link reaction

Answer 4

pyruvate is decarboxylated, NAD is reduced, forms acetate. Acetate combines with coenzyme A to form acetyl coenzyme A. 2 times for every Glucose.

Question 5

Krebs cycle

Answer 5

Acetyl coenzyme A combines with 4C compound, forms citrate 6C. citrate converted into 5C compound (CO2 released), dehydrogenation, NAD reduced. decarboxylation on 5C compound into 4C, dehydrogenation (1 FADH and 2 NADH)