D. Answer the following questions.
1. Why do animals reproduce?
2. Name two ways by which animals reproduce?
3. What are mammals? Give two examples.
4. Write a few lines on the structure of an egg.
5. Why does a frog lay its eggs in water?
6. Name two animals which do not care for their young ones.
7. What are nymphs? How do they grow into adult insects?
Answers
Answer:
1.Most importantly, reproduction is necessary for the survival of a species. ... This type of reproduction produces genetically-identical organisms (clones), whereas in sexual reproduction, the genetic material of two individuals combines to produce offspring that are genetically different from their parents.
2.Animals can reproduce in two different ways which are Asexual Reproduction and Sexual Reproduction. In Asexual Reproduction there is no formation of gametes and offsprings are genetically identical to the parent.
3.Mammals are a class of endothermic vertebrates. They have four limbs and produce amniotic eggs. Examples of mammals include bats, whales, mice, and humans.
4.Shell. The Shell our outer covering of the egg, is either white or brown. ...
Membrane. A membrane lines the shell and forms an air cell at the large end of the egg. ...
Aircell. On one side of the egg (broader), both these membranes separate to form an air cell. ...
Egg white. ...
Egg yolk. ...
Chalaza
5.A frog's eggs do not do not have a hard protective shell like in case of birds and reptiles. Instead, the frog's eggs are covered with a glycoprotein, which helps to keep the eggs moist. ... Therefore, frog lays its eggs in water to prevent them from getting dried up.
6.panda.
black bears.
7.Nymphs do not become pupae before becoming adults. They just grow larger. ... The adult form is prepared in the pupa, and comes out perfect. Some insects that are nymphs when they are young are grasshoppers, cockroaches, true bugs and dragonflies.
Explanation:
hope it helps you.
Answer:
if can answer a few only
Explanation:
1. To continue their breeds and their species.
5.Because frog is an aquatic animal and their babies can,t live without water in their first breath
6.Panda and Black Bears