6.3 Factors affecting photosynthesis

Question 1

destarching

Answer 1

leaving a plant in the dark for long enough for it to use up its starch stores

Question 2

control

Answer 2

a standard sample that you use as a comparison, to find the effect of changing a variable

Question 3

limiting factor

Answer 3

A factor that is in short supply, which stops an activity ( such as photosynthesis) happening at a faster rate

Question 4

arbitrary units

Answer 4

These are sometimes used on a graph scale to represent quantitative differences between values instead of ‘real’ units such as seconds or centimetres: this is usually because the real units would be very complicated to use