What are the internal factors of photosynthesis??how do they affect photosynthesis?
Answers
Light is essential for photosynthesis. Photosynthesis does not take place in dark. The sun is the main source of light energy. Both quality and
intensity of light are important for photosynthesis. •
(a) Light Quality: The light consists of rays of different wavelengths.
Only red and blue light are effective for photosynthesis. Green light is reflected or transmitted. Therefore, it does not play role in photosynthesis. Light of wavelength longer than 700 run is not effective for photosynthesis for green plants. Experiments of Engelmann proved that maximum photosynthesis occurs in the red and blue part of the spectrum.
(b) Light Intensity: Photosynthesis begins at very low intensity. It becomes maximum at bright daylight. But it decreases in strong light. Different plants require different intensity of light. Most of light reaching green leaves is reflected or transmitted. Thus only a small part of light is absorbed. Thus only about 0.5 to 1.5% of light energy is in photosynthesis. Thus light is not a limiting factor at high intensity.
Light is a limiting factor at low intensity. Thus the rate of photosynthesis increases with an increase in light intensity. High light intensities affect the rate of photosynthesis. It increases the temperature of the leaves. Therefore, rate of transpiration increases. The stomata are closed. It stops the . entry of CO2. Thus photosynthesis is stopped. Light also cause photorespiration. Photorespiration reduces the yield.
Carbon dioxideThe atmosphere is the chief source of carbon dioxide. It contains only 0.03 % of the gas by volume. It is very small amount. Therefore, CO, remain a limiting factor. The increase in the amount of carbon dioxide increases the photosynthesis. This increase is more rapid up to I % of carbon dioxide concentration. But it slows down beyond this point. Higher concentrations have an inhibitory effect on photosynthesis. It is clear that increase in concentration of CO, increases the yield of plant
Answer:
Many external and internal factors affect the rate of photosynthesis. The external or environmental factors at:A light intensity, carbon dioxide concentration and temperature. The internal factor influencing the photosynthesis is chlorophyll content of the leaves and protoplasmic factors.