Olympiad Test: Animals -2 - Class 4 MCQ

When a larva has eaten enough food and grows big enough, it pupates into the third body form, the pupa. While in this form, the beetle does not eat or move very much. The pupa just sits and waits while its insides rearrange into the form needed for the fourth and final body stage.

The nymph sheds its skin to transform itself into an adult. This process is called moulting.

The grasshopper life cycle only has three stages: egg, nymph, and adult. The process of going from egg to full adult grasshopper is called metamorphosis. A grasshopper's metamorphosis is incomplete, because it doesn't turn into a caterpillar.

The scaly skin of snakes helps them in crawling and protect the skin drying.

The correct combination is: Caterpillar - butterfly, nymph - cockroach, tadpole-frog Maggot- housefly.                         p−III,q−IV,r−I, s−II.

 

Explanation:
The correct answer is B: Lion, goat, and whale.
Here is the detailed explanation:
- Animals can be grouped based on their characteristics, habitats, or other similarities. To determine which set of animals represents a group, we need to consider their similarities or common features.
- Option A: Birds, butterfly, and frog: This set includes animals from different categories. Birds and butterflies are both flying animals, but frogs are amphibians. Therefore, this set does not represent a group of animals based on common characteristics or features.
- Option B: Lion, goat, and whale: This set includes animals from different habitats and classifications. Lions and goats are land animals, while whales are marine mammals. However, they are all mammals and share common characteristics such as being warm-blooded and having mammary glands. Therefore, this set represents a group of animals based on their shared characteristics as mammals.
- Option C: Lion, hen, and human beings: This set includes animals from different classifications. Lions and hens are animals, but human beings are humans. Humans are not considered animals in the scientific classification. Therefore, this set does not represent a group of animals.
- Option D: Tiger, sheep, and crocodile: This set includes animals from different classifications and habitats. Tigers and crocodiles are predators, while sheep is a herbivore. They also have different physical characteristics. Therefore, this set does not represent a group of animals based on common features.
In conclusion, the set of animals that represents a group is B: Lion, goat, and whale.

Answer:
The gnawing animals are those that have specialized teeth and jaws for chewing on hard materials such as wood, bark, and nuts. Based on this information, we can determine which of the following animals are gnawing animals:
1. Beaver: Beavers are well-known for their ability to gnaw through trees and build dams using their sharp incisors. They use their teeth to cut down trees and create their elaborate homes.
2. Rat: Rats are also gnawing animals. They have long, sharp incisors that continuously grow throughout their lives. They use their teeth to gnaw through various materials, including wood, wires, and pipes.
3. Squirrel: Squirrels are also considered gnawing animals. They have sharp incisors that they use to gnaw on nuts, seeds, and tree bark. This helps them access food sources and create nests in tree trunks.
4. Guinea pig: Guinea pigs, although they have teeth, are not typically considered gnawing animals. They have different types of teeth designed for grinding and chewing on vegetation rather than gnawing on hard materials.
Therefore, the correct answer is D: 1, 2, 3, and 4 as all of these animals have the ability to gnaw.

Birds build nests for various reasons, including shelter, protection, and a safe place to raise their young. Here are some key points explaining in detail where birds build their nests:
On the branches of tall trees:
- Many bird species, such as eagles and hawks, build their nests on the branches of tall trees.
- This location offers a vantage point for hunting and observing potential threats.
- The height of the tree provides protection from ground-dwelling predators.

X represents grasshopper, Y is butterfly and Z is rabbit.