Question

What special anatomical features are displayed by leaves of C₄ plants? How do they provide advantage over the structure of C₃ plants?

Answer 1

The C₄ plants have special anatomy in leaves. There is a sheath of enormous cells throughout the vascular bundles in the leaves. This is called Kranz Anatomy. Several membranes of cells around the bundle cell are particularly impregnated with chloroplast. The thick walls of these cells are impenetrable to gaseous exchange. Intercellular space is absent in the sheath. The bundle sheath provides an advantage to C₄ plants over C₃ plants. This sheath helps in increasing carbon dioxide concentration in the leaves. The relative concentration of carbon dioxide and oxygen influences the binding of this enzyme to a particular molecule. The high concentration of carbon dioxide in the leaves of these plants ensures that all the RuBisCO binds with carbon dioxide and there is no binding with oxygen. Thus, photorespiration does not take place in these plants. This helps in prevent wastage of aids and carbon fixation is highly productive in these plants. Eventually, these plants establish a higher percentage of biomass compared to the C₃ plants.