Q. A plant in your garden avoids photorespiratory losses, has improved water use efficiency, shows high rates of photosynthesis at high temperatures and has improved efficiency of nitrogen utilization. In which of the following physiological groups would you assign this plant :

Q. A plant in your garden avoids photorespiratory losses, has improved water use efficiency, shows high rates of photosynthesis at high temperatures and has improved efficiency of nitrogen utilization. In which of the following physiological groups would you assign this plant :

(a) C₃

(b) C₄

(c) CAM

(d) Nitrogen fixer

Solution :

Correct option : A Explanation of correct option: 1. Plants that grow in tropical dry areas undergo the C₄ pathway. Example: maize, sorghum. 2.In C₄ plants, the first product of CO₂ fixation is oxaloacetic acid (a four-carbon acid). 3.C₄ plants possess a distinct type of leaf anatomy called ‘Kranz’ anatomy in which the mesophyll cells form a cluster around the bundle-sheath. 4.C₄ plants show a high photosynthesis rate at high temperatures, efficiently utilize nitrogen and water, lack photorespiration, etc.