It is a pictorial representation of a content.
Above concept map gives an overview of the unit reproduction in animals of class eighth.
Think and discuss
Here are few brainstorming questions which will extend learning.Just try it……..(Hints are provided at the end in case if difficultly)
1.Mother gives birth to young ones but baby has characters of both parents.How is it possible?
2.Why are male gametes produced in huge numbers (in millions) while the female gametes produced are only few(one or two or in hundreds in few animals)?
3.In market eggs of hen are available but never eggs of dog or cat…… Why?
4.Although two cells called gametes fuse,the product formed is a single cell called zygote.why?
5.What happens if reproduction doesn’t occur?
6.What purpose does the tail in a sperm serve?
7.Why do fish ,frog etc., show external fertilization and reptiles, aves and mammals show internal fertilization?
8.How does fertilisation occur in animals which lay shelled eggs?
9.A frog has no tail.Why does it’s tadpole larva possess a tail?
10.If one sperm can fertilize only one egg, how are twins formed?
Hints
1.fusion of both male and female gametes.
2.Sperm is motile(mobility).
3.In hen, egg develops into young one
4.fertilization
5.It is the characteristic feature of living being
6.sperm comes in contact with egg or ovum
7.Adaptation
8.Frog egg
9.Amphibian nature
10.No.of zygotes
Sarithagn 