Join 60,000+ competitive exam aspirants
or with email
Your Cart
SubtotalтВ╣0
TotalтВ╣0
Examoogle тАв User тАв info@examoogle.com тАв EE-2024-8821
Chapter 1 of 12 тАв Page 1 of 248ЁЯФТ Protected PDF тАв Watermarked
Join 60,000+ competitive exam aspirants
Which of the following animals is NOT a mammal?
Lizard
Bat
Dolphin
Elephant
Lizard
A mammal is a vertebrate animal belonging to the class Mammalia, characterized by the presence of mammary glands, hair or fur, and being endothermic (warm-blooded). The lizard is a reptile, not a mammal, as it possesses scaly skin, is ectothermic, and lays amniotic eggs.
A mammal is a vertebrate animal belonging to the class Mammalia, characterized by the presence of mammary glands, hair or fur, and being endothermic (warm-blooded). The lizard is a reptile, not a mammal, as it possesses scaly skin, is ectothermic, and lays amniotic eggs.
Think of a mammal like a self-regulating heater that carries its own fuel (milk), whereas a lizard is like a solar-powered device that needs to sit in the sun to 'recharge' its metabolism.
MAMMALS: Milk, Air-breathing, Mothers nurse, Metabolism (warm-blooded), All have hair, Lung-breathing, Suckle young.
Metabolic┬аRateтИЭTbodyтАЛ тАФ representing the heat-regulated nature of endothermic mammals versus the environment-dependent ectotherms.
The class Mammalia is defined by key physiological traits: the presence of mammary glands to produce milk, a neocortex in the brain, three middle ear bones (malleus, incus, and stapes), and hair. In contrast, reptiles (like lizards) rely on external heat sources to regulate body temperature and lack the specialized glands found in mammals.
Mammals are endothermic, meaning they maintain a constant body temperature.
Reptiles are ectothermic, relying on the environment for thermal regulation.
All mammals, including marine mammals like dolphins and bats, breathe air using lungs.
Lizards belong to the class Reptilia, characterized by dry, scaly skin.
Mammals can survive in diverse, extreme climates due to internal temperature regulation.
High energy expenditure is required to maintain internal homeostasis in mammals.
Veterinary science and zoological classification.
Wildlife conservation and ecosystem monitoring.
| Feature | Lizard (Reptile) | Mammal |
|---|---|---|
Body Temperature Regulation | Ectothermic (Cold-blooded) | Endothermic (Warm-blooded) |
Outer Covering | Scales | Hair or Fur |
Dolphins are cetaceans, which are fully aquatic mammals, while bats are the only mammals capable of true flight.
Option B, C, and D are all mammals: Bats are chiropterans, dolphins are cetaceans, and elephants are proboscideans.
A is correct тАФ The lizard is a reptile, characterized by scaly skin and ectothermic metabolism, which excludes it from the class Mammalia.
When classifying animals in exams, always check for the presence of hair and mammary glands; even whales and dolphins, which lack visible fur, possess hair during early developmental stages and feed their young milk.
Get instant step-by-step AI explanations, full shift Previous Year Papers (SSC GD, RRB, SSC JE), and regional rank analysis on the official Examoogle App.
Free Download тАв 100K+ Aspirants