Monday, 30 April 2012

7th class-cbse english (An alien hand) Chapter-3 (The desert)

Answer following questions in short.

Q1) A camel can do without water for days together. How?
Ans1) Camels sweat very little; therefore they can do without water for days together. We need sweat to cool our body. Camels can tolerate a high body temperature so they don’t need to sweat. So, they can retain the water for a long period of time.

Q2) How do smaller desert animals fulfill their need for water?
Ans2) The smaller desert animals either get the water they need from plant juices or they eat other animals and get the water from their body.

Q3) In a desert the temperature rises during the day and falls rapidly at night. Why?
Ans3) The air in desert lands is extremely dry. The moistures in the air acts as a cover to protect the lands from the hot rays of the sun. In desert lands , this protective covering is absent. Therefore, the land get heats up quickly during the day due to the sun’s rays and cools down rapidly at night.

Q4) What is an Oasis?
Ans4) A green patch of land in the middle of a desert where a spring or well is surrounded by trees and plants is called an Oasis.

Q5) What are sand dunes?
Ans5) Sand dunes are heaps of sand with special shapes. They keep shifting their position across the desert by the strong winds.

Q6) What is the popular belief about deserts? What is the truth?
Ans6) The popular belief is that deserts are an endless stretch of sand without rain falls and vegetation. The truth is that the deserts have a different kind of vegetation. The plants and animals there have learned to survive in hot and dry condition.