Question

Consider the following four statements (a-d) about certain desert animals, such as kangaroo rat.
a) They have dark colour and high rate of reproduction and excrete solid urine.
b) They do not drink water, breathe at a slow rate to conserve water and have their body covered with thick hairs.
c) They feed on dry seeds and do not require drinking water.
d) 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?
A)c and d
B)b and c
C)c and a
D)a and b

Answer 1

Hint: Kangaroo rats are rodent animals that are generally nocturnal and are found in arid regions. They have small front legs and a large head. They weigh between 70 and 170 grams. They have a longer tail. They have fur-lined cheek pouches which help in storing food. The movement shown by kangaroo rats is bipedal. They are primarily seed-eaters.

Complete answer: Kangaroo rat is a desert animal. Their bodies are covered by hairs. They excrete urine, which is 20 times more concentrated than their plasma. Their body meets water requirements by metabolic processes such as from oxidation of carbohydrates, fats, and proteins. They feed on dry seeds. They conserve water by lowering their metabolic activity and thus reduces water loss through their skin and respiratory system. They remain in a cool burrow during day time to stay away from the heat. They extract water from the seeds. A half gram of water out of every gram of water can be extracted by kangaroo rats.
Xerophytic animals are the animals that live in the desert area and are adapted to various environmental conditions such as- the increase in body temperature reduces the heat flow from the environment, presence of thick hairs/fur which reduces the heat gain from the environment. These adaptations are necessary in order to protect themselves from the high temperature, to live without water, and to conserve water.
Thus, the correct option is Option A-c and d.

Note: Deserts are very dry places which do not receive much rainfall. They can be either hot or cold places. Animals living in the desert adapt themselves to survive with less amount of water or with no water at all. Such animals are- kangaroo rats, Bactrian camel, gecko, black widow spider, tarantula, Jackrabbit, fennec fox, etc.