Figure 13.10 shows the effect of light on the rate of photosynthesis. Based on the graph, answer the following questions: (c) What do C and D represent on the curve?
Explanation The limiting factors are the factors which affect the rate at which photosynthesis takes place. During low or high levels of any of the environmental factors such as light, temperature, carbon di oxide and temperature, the rate of photosynthesis are also effected. However, when the levels of the factors increase it cause to increase the rate of photosynthesis. But when rate of photosynthesis reaches an optimum or saturation level, the factors cease to affect the photosynthetic rate and a constant level is maintained. At point D an optimum level of photosynthesis is achieved due to required light intensity. At this level, maximum photosynthetic activity is reached. The rate of photosynthesis is does not changes further, even the light intensity increases. At point C, the increasing intensity of light does not affect the photosynthetic process as it has reached a saturation point. Intensity of light does not act on the process of photosynthesis beyond the saturation or optimum level. Final Answer C represents the maximum rate of photosynthesis that could be attained. D represents optimum intensity of light.
