Factors affecting photosynthesis Flashcards
What is a limiting factor?
A variable that limits the rate of a chemical reaction
How can the law of limiting factors be expressed?
At any given moment, the rate of a physiological process is limited by the factor that is at its least favourable value
Name 3 limiting factors associated with photosynthesis?
Light intensity, CO2 concentration and temperature
How is the rate of photosynthesis measured?
The volume of oxygen released by a plant or the volume of carbon dioxide taken up by a plant
When light is the limiting factor, what is the rate of photosynthesis directly proportional to?
Light intensity
When photosynthesis reaches a point where there will be no net exchange of gases into or out of the plant, what is this point referred to as?
The compensation point
What human activities increase the level of CO2 in the atmosphere?
Burning fossil fuels and deforestation
How does carbon dioxide concentration affect photosynthesis, particularly the light-independent reaction?
CO2 concentration affects enzyme activity, in particular the enzyme that catalyses the combination of RuBP with Carbon dioxide
What factor besides CO2 concentration affects enzymes used in photosynthesis?
Temperature
What is the optimum temperature for plants?
25 degrees
By how much is the rate of photosynthesis increased with every 10 degree rise in temperature?
The rate of photosynthesis is doubled
What apparatus can be used to measure the rate of photosynthesis?
A photosynthometer
