Factors Affecting Photosynthesis

Light Intensity

Concentration Of Carbon Dioxide

Temperature

Water Supply

LIGHT INTENSITYLIGHT INTENSITY

Light is essential during the light Light is essential during the light reaction of photosynthesis.reaction of photosynthesis.

When the concentration of carbon When the concentration of carbon dioxide and temperature are dioxide and temperature are controlled at constant level, the rate controlled at constant level, the rate of photosynthesis is directly of photosynthesis is directly proportional to light intensity up to a proportional to light intensity up to a certain point.certain point.

Concentration of carbon Concentration of carbon dioxidedioxide

Carbon dioxide is needed in Carbon dioxide is needed in the dark reaction as a raw the dark reaction as a raw material used in the synthesis material used in the synthesis of glucose if there is no other of glucose if there is no other factors limiting factors limiting photosynthesis and increase photosynthesis and increase in the concentration of carbon in the concentration of carbon dioxide results in an increase dioxide results in an increase in the rate of photosynthesis.in the rate of photosynthesis.

At a very high light At a very high light intensity, the rate of intensity, the rate of photosynthesis slows photosynthesis slows down because the down because the pigment chlorophyll pigment chlorophyll is damaged by ultra-is damaged by ultra-violet rays.violet rays.

TemperatureTemperatureThe dark reaction of photosynthesis is The dark reaction of photosynthesis is catalysed by the photosynthetic enzyme catalysed by the photosynthetic enzyme and therefore changes in temperature will and therefore changes in temperature will affect the rate of photosynthesis.affect the rate of photosynthesis.Generally, an increase of 10 degree Generally, an increase of 10 degree Celsius in the surrounding temperature Celsius in the surrounding temperature will doubled the rate of photosynthesis.will doubled the rate of photosynthesis.The optimum temperature for most of the The optimum temperature for most of the plants are between 25-30 degree celcius.plants are between 25-30 degree celcius.However, when the temperature is too However, when the temperature is too high the photosynthetic enzyme are high the photosynthetic enzyme are destroyed and photosynthesis stops destroyed and photosynthesis stops altogether.altogether.

WATER SUPPLYWATER SUPPLY

Water is needed for Water is needed for photosynthesis, however photosynthesis, however water is rarely the limiting water is rarely the limiting factor in photosynthesis factor in photosynthesis because the amount of water because the amount of water required is small.required is small.If water is not supplied, If water is not supplied, wilting occurs and the wilting occurs and the stomata is closed.This stomata is closed.This prevents the diffusion of prevents the diffusion of carbon dioxide into the carbon dioxide into the leaves.As a result the rate of leaves.As a result the rate of photosynthesis decreases as photosynthesis decreases as the lower concentration of the lower concentration of carbon dioxide becomes the carbon dioxide becomes the limiting factor.limiting factor.