Scientists measure the rate of photosynthesis by the volume of oxygen given off in a time ( say volume of oxygen given off per hour). There are three factors that can affect the rate of photosynthesis. These are:

·         Light

·         Temperature

·         Carbon Dioxide

We will look at the effects that each of these factors have on the speed of photosynthesis. If you increase light intensity then the rate of photosynthesis will increase. Likewise, if you increase the concentration of carbon dioxide (CO₂) the rate of photosynthesis will increase. However, they do reach a maximum and level out. If you had infinite carbon dioxide and an infinite light intensity a plant would not photosynthesise infinitely fast.                            

Temperature is a little different to the other two factors. There is a small temperature range where photosynthesis works best. If the temperature is too low photosynthesis will slow down or stop all together (shove a plant in the freezer and watch it die) or if the temperature is too high photosynthesis will slow down or stop all together (put a plant in the oven at gas mark one and watch it die)[i].