Page 8 - Reproduction in Animals

Activity 6.3

Get permanent slides of
hydra. Observe them using
hand lens or a microscope.
Look out for any bulges
from the parent body.
Count the number of
bulges that you see in
different slides. Also, note
the size of the bulges. Draw
the diagram of hydra, as
you see it. Compare it with
Fig. 6.11 : Budding in Hydra
the Fig. 6.11.

In each hydra, there may be one or
more bulges. These bulges are the
developing new individuals and they are
called buds. Recall the presence of buds
in yeast. In hydra too the new individuals
(a)
develop as outgrowths from a single
parent. This type of reproduction in
which only a single parent is involved is
called asexual reproduction. Since new
individuals develop from the buds in Dividing nucleus
hydra, this type of asexual reproduction
(b)
is called budding.
Another method of asexual
reproduction is observed in the
microscopic organism, amoeba. Let us
see how this happens.
You have already learnt about the
structure of amoeba. You will recall that (c)
amoeba is a single-celled organism
[Fig. 6.12(a)]. It begins the process of
reproduction by the division of its Daughter amoebae
nucleus into two nuclei [Fig. 6.12(b)].
This is followed by division of its body
into two, each part receiving a nucleus
[Fig. 6.12(c)]. Finally, two amoebae are
produced from one parent amoeba (d)
[Fig. 6.12(d)]. This type of asexual
Fig. 6.12 : Binary fission in Amoeba

REPRODUCTION IN ANIMALS 73

Rationalised-2023-24