Title: Limiting factors in photosynthesis - Biology Notes for IGCSE 2014
Headings: 
#44 Limiting factors in photosynthesis
Content: As light intensity increases, the rate of photosynthesis will increase, until the plant is photosynthesising as fast as it can. At this point, even if light becomes brighter, the plant cannot photosynthesise any faster. Over the first part of the curve ( between A and B ), light is a limiting factor. The plant is limited in how fast it can photosynthesise because it does not have enough light. Between B and C, light is not a limiting factor. Even if more light is shone on the plant, it still cannot photosynthesise any faster. Carbon dioxide
In photosynthesis CO2 is a key limiting factor. The usual atmospheric level of CO2 is 0.03%. In perfect conditions of water availability, light and temperature this low CO2 level holds back the photosynthetic potential. The more CO2 a plant is given, the faster it can photosynthesise up to a point, but then a maximum is reach.