Internal Factors Affecting Photosynthesis

Anatomy

Anatomy which favours the amount of CO₂ diffusion into collenchyma cells the intensity dilution of light and the rate of photosynthesis. Thickness of epidermis, size structure, position and frequency of stomata, distribution of vascular tissue and intercellular spaces, position and number of chloroplasts.

Chlorophyll

Essential for photosynthesis.

Carotenoids

Essential to prevent photo-oxidation which reduces photosynthesis

Age

Rate of photosynthesis increases with age of the leaf till maturation. Afterwards it begins to decrease.

Demand

Decreases if meristems is removed to decrease demand for photosynthesis. It increases at the time of increased synthetic activity.

Hormones

Cytokinin and gibberellins enhance the rate of photosynthesis while ABA decreases.

Translocation

The energy rich carbon compounds formed during photosynthesis- called photosynthates or photoassimilates are transported to all the organs and tissues of the plant body. This long distance transport of photosynthates through the phloem is called as translocation.

The photosynthates provide energy to the non-photosynthetic tissues through respiration. In storage organs, photosynthates are stored in the form of starch or as other carbohydrates.