Question

Identify the correct statement(s) in relation to $C_4$ photosynthesis.

• A. Kranz anatomy is an essential feature for $C_4$ plants.
• B. $C_4$ plants have higher water use efficiency than $C_3$ plants.
• C. Photorespiration can be minimized when $C_4$ pathway is in operation.
• D. All of the above.

Answer 1

The correct option is D All of the above.

Kranz leaf anatomy refers to the presence of two photosynthetic cell types namely bundle sheath (BS) cells and mesophyll (M) cells and is the characteristic of $C_4$ plants. Spatial separation of carbon dioxide fixation and RUBISCO activity in mesophyll and bundle sheath cells of $C_4$ plants respectively avoids photorespiration by concentrating $C{O}_2$ in bundle sheath cells. These plants can carry out photosynthesis even keeping the stomata closed and exhibit high water use efficiency. OAA is converted into malate in mesophyll cells. Thus, the correct answer is option D.