Given below are two statements

Statement I: C₃  plants are more efficient than C₄  plants in terms of carbon dioxide fixation

Statement II: C₄  plants are less water efficient and consume more amount of water then C₃  plans for same amount of CO₂  fixed.

In light of the above statements, choose the correct answer from the options given below

Solution

C₄  plants are actually more efficient than C₃  plants in terms of carbon dioxide fixation. C₄  plants have adapted a more efficient carbon fixation pathway that allows them to minimize photorespiration and increase photosynthetic efficiency, particularly in high-temperature and high-light conditions. C₄  plant loses half as much as water as a C₃  plant as C₄  plants need not to open their stomata for long to take in carbon dioxide due to high efficiency of the C₄  pathway and this reduces water loss due to transpiration. The water loss per gram of biomass produced with C₃  cycle is high (450-950). However, the water loss per gram of biomass produced with C₄  cycle is low (250-350)