B8.2 - The Rate Of Photosynthesis (Finishedish) Flashcards
What does a limiting factor for photosynthesis mean?
If something is a limiting factor it means that it is stopping photosynthesis from happening any faster
What are the limiting factors for photosynthesis?
Light intensity, CO2 concentration, temperature. Also chlorophyll
Why is light a limiting factor for photosynthesis?
Light provides the energy needed for photosynthesis to occur, so if there is not enough it will limit the rate of photosynthesis
As the light level is increased, how does the rate of photosynthesis change and why?
As the light level is raised, the rate of photosynthesis increases steadily up to a point. Beyond that it won’t make a difference (no longer increase) as co2 concentration or temperature has become the limiting factor
Why is co2 concentration a limiting factor for photosynthesis?
Co2 is a raw material needed for photosynthesis
How does the rate of photosynthesis change with increasing co2concentration?
As co2 concentration is increased then rate of photosynthesis will increase up to a point. But then the graph will flatten out as something else has become the limiting factor
Why is temperature a limiting factor for photosynthesis?
If the temperature is too low enzymes needed for photosynthesis will work more slowly. Too hot and the enzymes will be damaged and destroyed
At what temperature are enzymes for photosynthesis destroyed?
45 °C
What would vary the amount of chlorophyll in a plant?
- disease
- environmental stress such as lack of nutrients
These cause chloroplasts to be damaged or destroyed, or not enough chlorophyll is made so plants can’t absorb so much light
Distance
and light intensity are ___ to each other
Inversely proportional
What is the equation for light intensity?
Light intensity = 1/distance^2
