Consider the following four statements (i)–(iv) about certain desert animals such as kangaroo-rat. (i) They have dark colour and high rate of reproduction and excrete solid urine (ii) They do not drink water, breathe at a slow rate to conserve water and have their body covered with thick hairs (iii) They feed on dry seeds and do not require drinking water (iv) They excrete very concentrated urine and do not use water to regulate body temperature Out of these four, which two are correct?
- (i) and (ii)
- (ii) and (iii)
- (iii) and (i)
- (iii) and (iv)
Answer
(4) (iii) and (iv)
Solution
⇒ As per NCERT, the kangaroo rat in North American deserts is capable of meeting all its water requirements through its internal fat oxidation (water is a by-product), so it feeds on dry seeds and does not need to drink water — statement (iii) is correct.
⇒ It also has the ability to concentrate its urine so that a minimal volume of water is used to remove excretory products; it does not sweat or pant, i.e., it does not use water to regulate body temperature — statement (iv) is correct.
⇒ It does not excrete solid urine, and a thick hair coat, dark colour and slow breathing are not its water-saving adaptations — statements (i) and (ii) are incorrect.
Answer: (4)