Factors Affecting Rate Of Photosynthesis Flashcards
What are limiting factors?
Factors that effect the rate of photosynthesis when they’re at the shortest supply
So even if we have plenty of the other factors, the rate is reduced lower because of the limiting factor
3 factors that could be limiting
Light intensity at certain wavelengths
Temperature
CO2 concentration
Why is water loss not normally a limiting factor?
Because stomata can close to prevent loss of water
Light intensity
Higher light intensity of the wavelengths of light that are absorbed by pigments means more energy provided for LDR thus increases photosynthesis
Which reaction does temperature effect?
The LDR: dehydrogenase enzyme not effected by increasing Ek usually because it is immobilised in thylakoid membrane so increasing temp which increases Ek has no effect
Increasing temperature for the LIR
Increases the Ek of rubisco enzyme, increases successful collisions between rubisco active site and RuBP + CO2, increases number of E-S complexes formed in a guíen time, increases rate of reaction
Increasing temp too high means…
Enzymes denature = decreases rate of photosynthesis
Stomata close to reduce water loss so less CO2 enters = decreases rate
Permeability of thylakoid membrane decreases as it falls apart thus no H+ gradient formed = decreases rate
CO2 conc
Has optimum temp as more CO2 (substrate conc increased) so increased collisions between CO2 and rubisco etc
Why increasing CO2 conc not a good idea?
Because the stomata will close
How can we increase plant growth in agriculture?
Increase CO2 conc in greenhouses by burning fuel
Use glass to let light in
Trap heat to increase temp/ use heating and cooling systems
Structure for why a factor increases plant growth
This factor increases rate of photosynthesis/ amount of glucose produced in a plant
Because…
So the plants can respire more, obtaining more ATP for use in cell division for growth
