1. … how many finished cars can it make in a week?
If a car factory can make…
16 engines per week
40 seats per week
58 doors per week
33 windscreens per week
… how many finished cars can it make in a week?

2. The Law of Limiting Factors
When a process depends on two or more factors, the rate of that process is limited by the factor which is in shortest supply
The rate of photosynthesis in a plant can be limited by:
Light intensity
Availability of water
Availability of carbon dioxide
Availability of chlorophyll
Temperature

3. Photosynthesis and the Law of Limiting Factors
What you need to know:
What factors limit the rate of photosynthesis?
How do we explain why certain factors limit the rate of photosynthesis?
Can we use the law of limiting factors to explain experimental results? 
Question:
What does MRS GREN stand for?

4. Nutrition = Photosynthesis
What do the letters below stand for?
Remember: as living things plants are respiring all the time M
- movement R
- respiration S
- sensitivity G
- growth R
- reproduction E
- excretion
For plants
Nutrition = Photosynthesis N
- nutrition

5. How does the rate of bubbles produced vary as light intensity is increased?
No. of Bubbles per minute
Light Intensity
No. of Bubbles per minute
Light Intensity
No. of Bubbles per minute
Light Intensity
No. of Bubbles per minute

6. No. of Bubbles per minute
Increasing light intensity has no effect as rate of photosynthesis is limited availability of carbon dioxide, water or chlorophyll
Compensation point
Rate of photosynthesis equals rate of respiration
No. of Bubbles per minute
Increasing light intensity increases rate of bubbling (and photosynthesis)
Light Intensity
Any oxygen produced by photosynthesis is used up in respiration

7. Complete the questions on the Law of Limiting Factors and Photosynthesis worksheet

8. a. 2 units of glucose can be made by plant A
Question 1:
a. 2 units of glucose can be made by plant A
b. Light is in shortest supply (6 units of light are needed to make one unit of glucose)
c. D (B is limited by the availability of CO2)
d. 4 (it will be limited by the availability of water)
Question 2:
Number of Bubbles per Minute
Light Intensity
Increasing light intensity increases the rate of photosynthesis
Increasing light intensity has little to no effect. This is because the rate of photosynthesis is now limited by the availability of CO2/water/temperature

9. Amount of Carbon Dioxide in the Atmosphere (arbitrary units)
The graph below shows how the amount of CO2 in the atmosphere in the Northern Hemisphere changes through the year
Amount of Carbon Dioxide in the Atmosphere (arbitrary units)
Describe the changes seen in the graph
Suggest a reason for the changes seen in the graph