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A nimals That Lay Eggs

Animals that lay eggs are called oviparous animals. The parent animals sit on
the eggs to keep them warm. This is known as incubation. Frog, fish, snake,

lizard and insects like cockroach and butterfly are examples of animals which
reproduce by laying eggs.

Birds

Birds reproduce by laying eggs in their nests. They sit on the eggs to keep them
warm. The eggs then hatch and chicks come out. When they come out, they cannot
fly as they are featherless. Their parents take care of them until they develop

feathers and learn to fly.

Hen sits over eggs to keep them warm Hen with chicks

Structure of an Egg

The internal structure of all the eggs produced by
birds is similar. The egg-shell is the outer layer Egg Shell
of the egg that protects its inner contents. The

jelly-like white coloured material inside the egg Albumen
shell is called albumen. The yellow-part present
inside the albumen is called yolk. The yolk has

all the nutrients which are necessary for the Yolk
development of an embryo or the growing baby.
The embryo develops into the young one. The

stages of development from an embryo to an adult
form the life cycle of an animal.

Egg
Fish

Fish lay hundreds of eggs in water at a time. They take care
of their eggs but only a few eggs develop into babies because

some are eaten by larger fish or other animals. The source of
warmth for incubation of fish eggs are the sunrays.

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