Question

The period of long sleep of the polar bear during winter is called

Answer 1

the period of long sleep of the polar bear during winter is called hibernation

Answer 2

The period of long sleep of Polar Bear during winter is called hibernation or winter hibernation.

EXPLANATION:

Hibernation is the sleep period that helps the polar bears to save their energy and survive the winter season without eating much. During winters, the body temperature of the polar bears falls and the heartbeat and breathing slow down. So, when hibernating, the polar bears do not need to use much energy. The energy is later used when the hibernation period is over.