Question

Find out the correct statements among the following: A. In C4 plants photosrespiration is absent.
B. In the photorespiration pathway, there is no synthesis of ATP and NADPH.
C. C4 plants are photosynthetically more efficient plants.
D. Kranz anatomy is found in C4 and CAM plants.

• A. A and C only
• B. A, B and C only
• C. A, C and D only
• D. A only

Hint:

Understanding the different adaptations in photosynthetic mechanisms helps in appreciating how plants optimize their energy production under varying environmental conditions.

Answer 1

The Correct Option is A

Let’s evaluate each statement: - A) In C4 plants, photosrespiration is absent: This is true. C4 plants, such as maize and sugarcane, have mechanisms that minimize photorespiration by initially fixing carbon dioxide into a four-carbon compound, which effectively concentrates CO2 in the bundle sheath cells where the Calvin cycle takes place, reducing the oxygenase activity of Rubisco. - B) In the photorespiration pathway, there is no synthesis of ATP and NADPH: This is correct. Photorespiration consumes energy and reduces the efficiency of photosynthesis, as it does not produce ATP or NADPH but rather uses them, which makes the process costly for the plant. - C) C4 plants are photosynthetically more efficient: This is true. Due to their specialized biochemical and anatomical adaptations, C4 plants are more efficient in photosynthesis under high light intensity, high temperatures, and dry conditions. - D) Kranz anatomy is found in C4 and CAM plants: This is incorrect. Kranz anatomy, characterized by a wreath-like arrangement of bundle sheath cells surrounding the mesophyll cells, is specific to C4 plants. CAM plants do not exhibit Kranz anatomy; they have different adaptations for their photosynthetic pathway. Therefore, the correct statements are A and C.