Question

Why is transpiration considered as a necessary evil?

Answer 1

Transpiration is considered a necessary evil because it is both vital for a plant's survival and potentially harmful to it. It is necessary because it creates a powerful transpiration pull that helps in the upward conduction of water and minerals from the roots to the leaves, and it also regulates the plant's temperature by providing a cooling effect. However, it acts as an evil because it causes an enormous loss of water (nearly 98% of absorbed water) through evaporation. If the water availability in the soil is low, this continuous loss can lead to wilting, dehydration, and ultimately the death of the plant.