Flashcards
Class 8, Chapter 2 - Microorganisms: Friend and foe | NCERT
Flashcards for quick repetition. What are microorganisms. What diseases they cause and how to prevent them. Science class 8 chapter 2 exercise test and solutions.
Flashcards: 11
Played: 1016 times
Which microorganisms reproduce only inside cells of host organism?
bacteria
viruses
fungi
protozoa
algae
Which diseases are caused by protozoa?
dysentery
cold
tuberculosis
malaria
influenza
Amoeba is a representative of:
Fungi
Algae
Bacteria
Protozoa
Which microorganisms may be multicellular?
bacteria
algae
fungi
protozoa
Which statements are true?
1. Microorganisms are used in agriculture for fixing nitrogen.
2. Fungi is used in curd production.
3. Yeast produces nitrogen during respiration.
1. Microorganisms are used in agriculture for fixing nitrogen.
What is fermentation?
It is a process of conversion of
. . . . . . . .
into
. . . . . . . .
.
It is a process of conversion of sugars into alcohol.
Match a scientist with his discovery
Alexander Fleming
penicillin
Louis Pasteur
fermentation
Edward Jenner
smallpox vaccine
Robert Koch
Bacillus anthracis
Describe process of milk pasteurisation.
Milk is heated to about
. . . . . . . .
for
. . . . . . . .
seconds and then
. . . . . . . .
chilled.
Milk is heated to about 70°C for 15 to 30 seconds and then suddenly chilled.
AIDS is caused by:
a bacteria
a protozoa
a fungi
a virus
How do we call insects and animals that can pass a diseasce causing microbes to us?
carriers
How much of the Earth's atmosphere is made up of nitrogen?