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Published on: 24/08/2019
Microorganisms Friend and Foe
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Questions + Answers key
Take MCQ Science Test
1.
Protozoans cause serious diseases such as _______ and ________.
2.
Some _______ and _______ present in the soil fix nitrogen from the atmosphere.
3.
Alcohol is produced with the help of________________
4.
Blue green algae fix __________ directly from air and enhance fertility of soil.
5.
Microorganisms can be seen with the help of a ____________________
6.
Which is the plant disease caused by microorganisms?
Measles
Small pox
Citrus Canker
Polio
7.
Which is not a communicable disease?
Diabetes
Chicken pox
Tuberculosis
Cholera
8.
Nitrogen fixation is brought about by :
blue-green algae
bacteria
both (a) and (b)
none of these
9.
This micro-organism is used for the large-scale production of alcohol, wine and acetic acid:
amoeba
paramecium
chlamydomonas
yeast
10.
This bacterium promotes the formation of milk into curd:
rhizobium
lactobacillus
aedes
all
11.
Pathogenic microorganisms present in host cells are killed by medicines called
pain killer
antibodies
antibiotics
vaccines
12.
The disease caused by a protozoan and spread by an insect is
dengue
malaria
polio
measles
13.
Alcohol is produced with the help of
sodium chloride
yeast
nitrogen
carbon dioxide
14.
Carrier of malaria-causing protozoan is
female Anopheles mosquito
cockroach
housefly
butterfly
15.
Yeast is used in the production of
sugar
alcohol
hydrochloric acid
oxygen
16.
Malaria
17.
Biological nitrogen fixers
18.
Penicillin
19.
Rhizobium
20.
Bacteria
21.
Viruses can be seen by simple microscopes.
22.
Microorganisms can be found only in air and water.
23.
Foot and mouth disease is a bacterial disease in animals.
24.
Microorganisms can be seen with naked eyes
25.
All microbes are disease causing
1.
( )
Typhoid and Tuberculosis
2.
( )
bacteria, blue-green algae
3.
( )
yeast
4.
( )
nitrogen
5.
( )
microscope
6.
(c)
Citrus Canker
7.
8.
(c)
both (a) and (b)
9.
(d)
yeast
10.
(b)
lactobacillus
11.
(c)
antibiotics
12.
(b)
malaria
13.
(b)
yeast
14.
(a)
female Anopheles mosquito
15.
(b)
alcohol
16.
( )
Female Anopheles
17.
( )
Increases soil fertility
18.
( )
Mould
19.
( )
Fixing nitrogen
20.
( )
Causing cholera
21.
(a)
22.
(b)
23.
(b)
24.
(b)
25.
(b)
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CBSE 8th Standard CBSE Subjects
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