Instead of migrating in response to cold weather, some organisms have the ability to enter a state of deep sleep. The animal's body temperature drop and activities slow down to conserve energy. This process is known as - * immigration
coma
winter slumber
hibernation

Hibernation is the answer

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Urban growth invariably feeds increased commercialization and industrialization. it requires continually expanding land areas. when urbanization rates are high, and countries do not have the institutional and managerial capacities or economic wherewithal to manage such rapid growths, they exert intense pressure on the types and nature of the resulting settlements. they contribute to the development of overcrowded slums and shanty towns without adequate essential services and necessary infrastructure.-by asit k. biswas and cecilia tortajada

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