Respiration

Question 1

Glycolysis

Answer 1

Glycolysis takes place in cytoplasm
Glucose phosphorylated
Provides activation energy
Phosphorylated glucose hydrolysed to form 2 triose phosphate Triose phosphate oxidised by removal of hydrogen
Hydrogen transferred to NAD to form NADH
2 pyruvate molecules made
Substrate level phosphorylation produces 2 ATP

Question 2

Link reaction

Answer 2

Pyruvate is decarboxylated to form acetyl
Hydrogen is removed and attached to NAD to form NADH
Acetyl is bound to Coenzyme A

Question 3

Kerbs cycle

Answer 3

Occurs in the mitochondria
Pyruvate enters the mitochondria by active transport
Acetyl coenzyme A delivers acetyl
Acetyl combines with a 4-carbon molecule
A 6-carbon molecule is formed
Coenzyme A is released to pick up more acetyl
The 6-carbon molecule is decarboxylated and oxidised twice
2 NAD are reduced/NADH is produced
To form a 4-carbon molecule
The 4-carbon molecule is oxidised
Reduced NAD is produced/NADH is produced
Reduced FAD is produced/FADH is produced
A molecule of ATP is made by substrate level phosphorylation
The 4-carbon molecule is rearranged to make the original 4-carbon molecule

Question 4

Oxidative phosphorylation

Answer 4

Krebs cycle / link reaction produces reduced NAD and reduced FAD Electrons released from NADH and FADH
Electrons pass along electron transport chain
Through series of redox reactions
Energy is released from electrons Protons/H+ move into intermembrane space Protons/H+ diffuse through ATP synthase
To form ATP from ADP and Pi