Photosynthesis: Limiting Factors

Question 1

Light intensity

Answer 1

• affects LDR and LIR
• LDR needs light for chlorophyll photoionisation and water photolysis
• LIR needs ATP and NADPH from the LDR

Question 2

Temperature

Answer 2

• affects LIR
• too hot denatures Rubisco
• too cold not enough KE for rubisco to work

Question 3

CO2 conc.

Answer 3

• affects LIR
• one of the reactants entering calvin cycle

Question 4

Solution

Answer 4

• Artificial light
• Paraffin/fuel burners: maintains optimum heat and produces CO2