Topic 5A - Respiration & Photosynthesis

Question 1

Where does anaerobic respiration happen?

Answer 1

cytoplasm - no oxygen needed

Question 2

cellular respiration (including both an/aerobic)

Answer 2

the process (es) that convert glucose into ATP, which releases small amounts of energy from ATP hydrolysis

Question 3

4 stages of aerobic resp

Answer 3

Glycolysis [in cytoplasm]
Link reaction
Krebs cycle
Oxidative phosphorilation

• anaerobic only uses glycolysis

Question 4

Desc. glycolysis & see drawn notes

Answer 4

• glucose enters cyto

1. Two ATP molecules hydroIyse to release 2 phosphate molecules to phosphorylise glucose {6 carbon molecule} > provides energy to activate glucose AND lowers activation energy for next enzyme-controlled reactions.
2. The phosphorylated glucose is unstable so breaks into 2 triose phosphates { 3 carbon molecule }
3. EACH triose phosphate is paired with the synthesis of 2 ATP molecules and it’s also oxidised as loses a H so NAD can be reduced
4. This turns it into 2 pyruvate molecules

• could be asked for the net gain of some molecules such as ATP, which is 2 as 2 are hydrolysed in the beginning (-2), and +4 made later

Question 5

Describe the link reaction and how pyruvate is moved into the place of reaction

Answer 5

• Actively transported into matrix for reaction
  pyruvate is oxidised (as NAD is reduced) into acetate by a condensation reaction, producing CO².
  3 carbon molecule into 2 carbon molecule.

Acetate combines with coenzyme A to be moved to Krebs cycle (acetyl coenzyme A)