Olympiad Test: Animals - 2 - Class 5 MCQ

Amphibians are animals that can live both on land and in water. Examples include frogs, toads, and salamanders. They have adaptations that allow them to survive in both environments.

• Option A (Aquatic animals) live only in water.
• Option C (Arboreal animals) live in trees.
• Option D (Aerial animals) live in the air, such as birds or bats.

Thus, the correct answer is Option B: Amphibians.

Fish are covered in scales, which provide protection and help reduce friction in water, allowing them to swim more efficiently. Scales also help protect the fish's body from parasites and environmental damage.

• Option A (Feathers) are found on birds, not fish.
• Option C (Shell) is found on animals like turtles, not fish.
• Option D (Wool) is found on animals like sheep, not fish.

Thus, the correct answer is Option B: Scales.

Carnivores are animals that primarily eat other animals. Eagles and tigers are examples of carnivores because they hunt and eat other animals for food.

• Option A (Zebra and deer): These are herbivores, as they eat plants.
• Option C (Butterflies and mosquitoes): These insects are not primarily carnivores; butterflies feed on nectar, and mosquitoes feed on blood but are not classified as full carnivores.
• Option D (Cows and goats): These are herbivores, as they eat plants.

Thus, the correct answer is Option B: Eagles and tigers.

Camouflage is a survival mechanism that helps animals blend in with their surroundings, making it harder for predators to spot them, or helping them sneak up on prey. It helps animals hide and avoid danger.

• Option A (To stay warm) is not the primary purpose of camouflage.
• Option B (To move quickly) is not related to camouflage; it refers to the animal's agility or speed.
• Option D (To communicate with others) is not the purpose of camouflage; animals communicate through sounds, colors, or behaviors, not by blending in.

Thus, the correct answer is Option C: To blend with surroundings.

Fish use gills to breathe. Gills allow them to extract oxygen from water, which is necessary for their survival.

• Option A (Frog): Frogs use lungs for breathing when on land and may use skin and gills during their aquatic larval stage.
• Option B (Whale): Whales are mammals and breathe air using lungs, not gills.
• Option D (Butterfly): Butterflies breathe through tiny openings called spiracles, not gills.

Thus, the correct answer is Option C: Fish.

The primary function of an elephant's large ears is to help them stay cool. The ears act like natural cooling fans, as the blood vessels in the ears help regulate body temperature by dissipating heat.

• Option A (To hear better) is not the primary function; although elephants have excellent hearing, their large ears are more important for cooling.
• Option C (To help them swim) is not correct; elephants can swim, but their ears are not used for swimming.
• Option D (To look bigger) is not the main purpose of their large ears.

Thus, the correct answer is Option B: To stay cool.

Butterflies use a proboscis, which is a long, coiled tube-like structure, to feed. They use it to suck nectar from flowers. The proboscis uncoils when feeding and acts like a straw.

• Option A (Hooked beak) is found in birds, not butterflies.
• Option B (Sharp teeth) is not a feature of butterflies.
• Option D (Gills) are used by aquatic animals like fish, not butterflies.

Thus, the correct answer is Option C: Proboscis.

Polar bears have a thick layer of fur that provides insulation to protect them from the cold. Underneath their fur, they also have a layer of fat (blubber) that helps keep them warm in freezing temperatures.

• Option A (Wool) is not the type of covering polar bears have.
• Option C (Scales) are found on reptiles, not mammals like polar bears.
• Option D (Feathers) are found on birds, not mammals.

Thus, the correct answer is Option B: Fur.

Insects breathe through small openings called spiracles. These spiracles are located on the sides of their bodies and allow air to enter and exit, helping with respiration. The spiracles lead to a network of tubes (tracheae) that deliver oxygen to the insect's tissues.

• Option B (Gills) are used by aquatic animals like fish, not insects.
• Option C (Shell) is the hard outer covering of some animals, like mollusks, not related to breathing.
• Option D (Plates) are not related to breathing in insects.

Thus, the correct answer is Option A: Spiracles.

Hibernation is the long winter sleep that some animals, such as bears and certain rodents, go through to conserve energy during the cold months when food is scarce. During hibernation, an animal's metabolism slows down, allowing it to survive on its stored body fat.

• Option B (Nap) refers to a short sleep, not a long winter sleep.
• Option C (Nocturnal) refers to animals that are active during the night, not related to winter sleep.
• Option D (None of these) is incorrect because the correct answer is hibernation.

Thus, the correct answer is Option A: Hibernation.