Page 102 - Science Class 08

ASEXUAL REPRODUCTION

Asexual reproduc on is a mode of reproduc on
in which the new offspring are produced from a
single parent. This mode of reproduc on is
generally observed in single-celled organisms.

Here no fusion of gametes is involved. A single
parent divides into two or more daughter cells.
The offspring produced are iden cal to each
other, both physically as well as gene cally. Dividing
nucleus
Hence, they are called clones. Also, they are
exact copies of their parent cell.

Features of Asexual Reproduc on

v Only a single parent is involved.
v No gamete forma on or fer liza on is
involved. Daughter

v The whole process takes place in less me; nucleus
not lengthy as the sexual reproduc on.
Binary Fission in Amoeba
v Offspring are exact copies of a parent,
there is no varia on. Budding
v Offspring growth is rapid. This is another type of asexual reproduc on

Asexual reproduc on system can be categorised found in hydra and other single-celled
mainly into: organisms. In a full grown hydra, a small
projec on is formed in the side of body. It is
v Fission
called bud. It grows to a small hydra within two
v Budding days. It detaches from the main body and starts

Fission it independent living.

In this method of asexual reproduc on, the
parent cell splits into two new ones. Both the
new split cell turn into new individuals. This
method of reproduc on is called binary fission.
It occurs in most unicellular organisms like
amoeba and parameciums. Amoeba is a single- Budding in Hydra

celled organism. It begins the process of
reproduc on by the division of its nucleus into
two nucleus. This is followed by division of its
body into two, each part receiving is produced When a certain body part of human beings
from one parent amoeba. affected by cancer, it means there is an
overgrowth of certain bacteria.

102 Science-8