Reproduction of Reproduction of animalsanimals

Why do animals Why do animals reproduce?reproduce?

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Animals die…

• All animals die when they get old.

•Some animals die in natural disasters.

•Some die when there is no food or water.

•Some are killed by other animals.

If animals do not reproduce,

• they will become…

Extinct

How do animals How do animals reproduce?reproduce?

Animal ReproductionAnimal Reproduction

The egg of the female animal isfertilised by the sperm of the male animal.

Animals reproduce in two Animals reproduce in two ways:ways:

1.By laying eggsThe mothers lay the fertilised eggs and hatch them.

They lay a large number of eggs each time.

Which comes first? Which comes first? Eggs or chicks?Eggs or chicks?

What is inside a What is inside a chicken’s egg?chicken’s egg?

•Shell•Egg white•Yolk•Embryo

•The fertilised egg develops in the mother’s body and becomes an embryo. •The mother gives birth to the baby after a period of time. The newborn baby feeds on its mother’s milk.

2. By giving birth to the you2. By giving birth to the youngng

How do these How do these animals animals

reproduce?reproduce?

Which animal gives birth Which animal gives birth to its young?to its young?

Which animal below Which animal below lay eggs?lay eggs?

Birds, insects and fishBirds, insects and fish lay eggs.lay eggs.

MammalsMammals give birth to their y give birth to their young.oung.

The Chinese University of Hong The Chinese University of Hong KongKong

Producer:Producer: Fong Pui Ting KarenFong Pui Ting Karen (99236240)(99236240)

Postgraduate Diploma of Education (Primary)Postgraduate Diploma of Education (Primary)

DEP5114A (2000-2001)DEP5114A (2000-2001)

Professor Mak Se YuenProfessor Mak Se Yuen

9 April, 20019 April, 2001

The EndThe End

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