Chapter 4: Animal Kingdom

Ans. Birds have undergone many structural adaptations or modifications to suit their aerial life. Some of these adaptations are as follows:  

1.They have a Streamlined body for rapid and smooth movement. 

2.Covering of body with feathers for insulation. 

3.Their forelimbs are modified into wings and their hind limbs are used for walking, perching, and swimming. 

4.The presence of pneumatic bones to reduce weight.

5.Presence of additional air sacs to supplement respiration.

Ans. The number of eggs produced by an oviparous mother will be more than the number of young ones produced by a viviparous mother. This is because, in oviparous animals, the development of young ones takes place outside the mother’s body. Their eggs are more prone to environmental conditions and predators. Therefore, to overcome the loss, more eggs are produced by mothers so that even under harsh environmental conditions, some eggs might be able to survive and produce young ones. On the other hand, in viviparous organisms, the development of young ones takes place in safe conditions inside the body of the mother. They are less exposed to environmental conditions and predators. Therefore, there are more chances of their survival and hence, less number of young ones is produced compared to the oviparous animals.

Ans. The body segmentation has first appeared in the phylum, Annelida (annulus meaning little ring)

Ans. 

Ans. The list of some animals that are found parasitic on human beings is as follows: