Photosynthesis in Opuntia is done by

Removal of soil by the action of wind and water is known as

They are dominant plants of the cold desert

Choose incorrect sentence

In summer, when out side temperature is more than our body temperature, we sweat profusely. The resulting evaporative cooling, similar to what happens with a desert cooler in operation, brings down the body temperature. In winter when the temperature is much lower $37^o C$, we start to shiver a kind of exercise which produce heat and raises the body temperature. They are called.