Page 21 - Genius Kidz Prudence Learning Sc-8
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asexual reproduction. But division by substrate. Cheese, yoghurt and butter
binary fission is one of the common are all produced by fermentation.
methods. (b) Digestion of food : Bacteria help in the
Binary Fission : digestion of cellulose in ruminants e.g.,
Enlargement of a bacterial cell cows and buffalos.
(c) Nitrogen fixation : Nitrogen fixing
bacteria live in the nodules of
leguminous plants. They convert
Is followed by division of nucleus
atmospheric nitrogen into nitrates and
thus make them available for plants.
Examples of nitrogen fixing bacteria
Followed by division of parent cell into two include Rhizobium.
daughter cells. (d) Maintenance of fertility of soil :
Bacteria are decomposers. They decay
dead remains of living beings and add
up the decomposed matter to the soil
thus maintaining its fertility.
(e) Medicinal application : Bacteria or their
products that inhibit the growth of
other microbes or kill them are called
antibiotics. Thus antibiotics can be used
for the treatment of microbial diseases.
Examples of antibiotics include
Streptomycin and Gramicidin.
(f) Industrial uses : Bacteria are useful in
tobacco, leather and jute industries.
Tanning is done with the help of
bacteria. In the jute industry, jute plants
are submerged in water, where
bacterial action separates the fibres
Binary Fisson
from rest of the tissues.
Bacteria are a friend
Bacteria as a foe
(a) Fermentation : Curding of milk is (a) Bacterial diseases : Bacteria can cause
achieved with the help of a bacteria diseases. Some of the examples of
called Lactobacillus. Wine, vinegar, bacterial diseases are as follows :
beer, etc. all are manufactured by the
action of bacteria on the corresponding (i) Tuberculosis : Caused by Myco-
bacterium tuberculosis
More germs are transferred while shaking hands than while kissing.
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