NCERT Book Class 8 Science Chapter 6 Reproduction in Animals

REPRODUCTION IN ANIMALS

D
o you recall the processes of Table 6.1
digestion, circulation and
respiration which you have S. No. Animal Young one
studied in your previous classes? These 1. Human Baby
processes are essential for the survival
of every individual. You have also learnt 2. Cat
about the process of reproduction in 3. Dog
plants. Reproduction is essential for the
continuation of a species. Imagine what 4. Butterfly
would have happened if organisms had 5. Hen Chick
not reproduced. You will realise that
reproduction is very important as it 6. Cow
ensures the continuation of similar 7. Frog
kinds of individuals, generation after
generation. Just as in plants, there are two modes
You have already learnt in your by which animals reproduce. These are:
previous class about reproduction in (i) Sexual reproduction, and
plants. In this chapter, we shall learn (ii) Asexual reproduction.
how reproduction takes place in
animals. 6.2 Sexual Reproduction
6.1 Modes of Reproduction Try to recall reproduction in plants
which you studied in Class VII. You will
Have you seen the young ones remember that plants that reproduce
of different animals? Try to name some sexually have male and female
of the young ones by completing reproductive parts. Can you name these
Table 6.1 shown in examples at S. No. parts? In animals also, males and
1 and 5. females have different reproductive parts
You must have seen the young or organs. Like plants, the reproductive
ones of various animals being born. parts in animals also produce gametes
Can you tell how chicks and that fuse to form a zygote. It is the zygote
caterpillars are born? How are kittens which develops into a new individual.
and puppies born? Do you think that This type of reproduction beginning
these young ones looked the same from the fusion of male and female
before they were born as they do now? gametes is called sexual reproduction.
Let us find out. Let us find out the reproductive parts