A limiting factorA factor which, if in short supply limits or reduces the rate of photosynthesis, eg temperature, light intensity and carbon dioxide concentration. is simply anything in short supply that prevents photosynthesis occurring at its maximum rate.
If photosynthesis occurs more slowly in plant cells then a lower quantity of sugar will be produced and the quantity of chemical energy available for cell growth will be reduced.
There are three important factors that can limit the rate of photosynthesis:
light intensity
carbon dioxide concentration
temperature
Investigating limiting factors - Testing for starch
We can investigate the limiting factors of photosynthesis by placing leaves in different conditions and testing for the presence of starch.
Iodine turns from brown to blue-black in the presence of starch, so we can use iodine to test if starch is produced in different conditions.
Watch the video below to see how to carry out this practical experiment.
