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Birds Life cycle of a hen

All the birds reproduce by laying eggs. An egg has a
hard protective outer shell. Within the shell there is a
white jelly–like substance called albumin. Inside the
albumin there is yellow liquid called yolk. It contains
food for growing chick or embryo. Birds lay eggs in
the nest. Then the parent sits on the eggs to give
warmth. This is known as incubation. With enough
warmth the egg's shell break out and a young one
comes out. This is called hatching of egg. When the
baby bird comes out of the egg, it can not fly. Parents
take care of the baby bird until it can fly.

Insects

Insects also reproduce by laying eggs. The
young ones of insects are different from their
adult. They undergo many changes and then
grow into an adults. This process is known as
metamorphosis. Insects like butterfly and
cockroaches reproduce in this way.
The butterfly lays egg on leaves. Inside each egg

caterpillar grows. Then the eggs hatch into a

caterpillar or larva.

The caterpillar keeps eating all the time and

grows bigger and fatter. Then it stops eating and Life cycle of butterfly
starts spinning a silk thread from a hole below

its mouth. This becomes a pad known as cocoon. Then the caterpillar curls inside a

cocoon and goes for sleep. This stage is known as pupa. After one or two days pupa

bursts and an adult butterfly comes out.

Frog

The frog lays a large number of eggs in water. These eggs hatch into tadpoles. Tadpole
has tail but no legs. It looks like a tiny fish and breathe through gills. After a few weeks
the tadpole loses its tail and develops legs. Soon it begins to look like its parent. When
it grows fully into an adult it comes out of the pond and starts to live on land and in
water also.

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