Photosynthesis Flashcards
What (in the leaves) absorbs light energy?
Chlorophyll
What sort of reaction is photosynthesis?
Endothermic
What is the word equation for photosynthesis?
Carbon dioxide + water -> glucose + oxygen
(Light above arrow)
What is the symbol equation for photosynthesis?
6CO₂ + 6H₂O -> C₆H₁₂O₆ + 6O₂
(Light above arrow)
What is a limiting factor?
Anything that limits the rate of reaction when in short supply (less of factor = less of product)
What are the limiting factors of photosynthesis?
- Temperature
- Light intensity
- Carbon dioxide concentration
- Amount of chlorophyll
If there’s less chlorophyll, what will happen to the rate of photosynthesis?
Decrease
If there’s less light, what will happen to the rate of photosynthesis?
Decrease
If there’s a lower temperature, what will happen to the rate of photosynthesis? Explain why.
Rate decreases - reactant molecules have less kinetic energy
What controls photosynthesis?
Enzymes
Why does photosynthesis rate decrease at a high temperature?
Enzymes that control the reaction are denatured so rate decreases
If there’s more carbon dioxide, what will happen to the rate of photosynthesis?
Increase
What eventually happens in photosynthesis?
A factor becomes limiting - often carbon dioxide
If there’s no light, what will happen to the rate of photosynthesis?
Decrease - photosynthesis will not happen
What can limiting factors do?
Interact
As distance from light source increases, what decreases? What sort of relationship is this?
Light intensity - inverse relationship
How do you work out light intensity?
Light intensity ∝ 1/distance²
What is an example of the control of limiting factors?
Commercial greenhouse:
They want the highest possible rates of photosynthesis to grow plants as quickly as possible.
More photosynthesis -> higher yield -> higher profit
Name 3 uses of glucose produced in photosynthesis.
- Converted into insoluble starch for storage.
- Produces lipids for storage.
- Produces amino acids for protein synthesis.
- Produces cellulose to strengthen cell walls.
- For respiration to release energy.
