1. Food Supply, Plant Growth and Productivity - The Calvin Cycle

Question 1

Describe step 1 of the Calvin cycle

Answer 1

The enzyme RuBisCo fixes carbon dioxide by attaching it to ribulose biphosphate (RuBP)

Question 2

Describe step 2 of the Calvin cycle

Answer 2

The intermediate produced is phosphorylated by ATP and reduced by hydrogen from NADPH

Question 3

Describe stage 3 of the Calvin cycle

Answer 3

Glyceraldehyde-3-phosphate (G3P) is formed

Question 4

Describe stage 4 of the Calvin cycle

Answer 4

G3P is used to regenerate RuBP and for the synthesis of glucose

Question 5

What 3 things could happen to the glucose?

Answer 5

It may be synthesised into starch or cellulose or pass to other biosynthetic pathways to form a variety of metabolites, or used as a respiratory substrate