Question

Which one of these animals is not a homeotherm?
A) Camelus
B) Macropus
C) Psittacula
D) Chelone

Answer 1

Hint: Homeotherms have no stable body temperature. Their internal body temperature is often, though not necessarily, higher than the immediate environment. The organism that shows this type of temperature regulation is a plant commonly known as the turtle head.

Complete answer:
Homeotherms are organisms that maintain a constant internal body temperature within a certain range. These animals have a steady continuous body temperature that is completely independent of the ambient environment. Their body temperature fluctuates as they pass through varying temperatures in different environments. Therefore, they have no stable body temperature. Therefore, these species are unable to live at high temperatures. Cold-blooded animals include invertebrates, reptiles, birds, amphibians, insects and others. These species are classified as poikilothermic species. There are mainly two categories of animals that are endothermic and ectothermic. The endothermic animals are warm-blooded animals and ectothermic animals are cold-blooded animals. Homoeothermic animals have constant body temperature regardless of external influence and they normally have high body temperature. Homoeothermic animals are endothermic or warm-blooded animals. Poikilothermic animals are opposite to the homoeothermic animals as their internal body temperature keeps changing. They cannot regulate their own body temperature. Chelone is an example of a homeotherm because they can not regulate their internal body temperature.
i. Macropus: It is a marsupial, so it is a homeotherm.
ii. Psittacula (parrot): it is an ave, therefore, it is a homeotherm as well.
Hence, the correct answer is option D.

Note: Chelone is a genus of four species of perennial herbaceous plants native to eastern North America. Their flowers vary in colour from red to white or from purple to pink. It is more closely related to other members of the family such as snapdragon, foxglove, etc.