Unit 3.3 Photosynthesis

Question 1

Name the two stages that happen in photosynthesis

Answer 1

1. Light Reaction
2. Carbon Fixation

Question 1

Describe stage 1

Answer 1

Light energy from the sun is trapped by chlorophyll in the chloroplasts and is converted into chemical energy which is used to generate ATP
Water is split to produce hydrogen and oxygen
Oxygen diffuses from the cell
Hydrogen and ATP are needed for the next stage

Question 1

Describe stage 2

Answer 1

It is an enzyme-controlled reaction. The hydrogen and ATP produced in the light reaction combine with carbon dioxide to produce glucose

Question 1

What can the chemical energy in sugar be used for

Answer 1

The chemical energy in sugar can be used for
1. Respiration
2. Starch (storage)
3. Cellulose (structural)

Question 1

Explain limiting factors

Answer 1

Whatever is in the least supply for photosynthesis will limit the rate of photosynthesis and plant growth

Question 1

What are the limiting factors

Answer 1

1. Carbon dioxide concentration
2. Light intensity
3. Temperature

Question 2

Explain limiting factors

Answer 2

Whatever is in least supply for photosynthesis will limit the rate of photosynthesis and plant growth