Factors which play significant role in the formation of major biomes are

Consider the following four statements $(1-­4)$ about certain desert animals such as kangaroo rat.

$(1)$ They have dark colour and high rate of reproduction and excrete solid urine.

$(2)$ They do not drink water, breathe at a slow rate to conserve water and have their body covered with thick hairs.

$(3)$ They feed on dry seeds and do not require drinking water.

$(4)$ They excrete very concentrated urine and do not use water to regulate body temperature.

Which two of the above statements for such animals are true ?

Which is the main causative factor of desertification

Differentiation of various tissue and organs in response to light is called

 Give scientific reasons : Majority of fresh water organisms have contractile vacuoles while marine organisms lack them.

- It has the ability to concentrate its urine.

- It provide water requirements from its internal fat oxidation.

- It is present in American desert.