Chapter 2
Microorganisms: Friends and enemies
1) Fill in the blanks -
Answer:
a) Microorganisms can be seen under a microscope .
b) Blue-green algae increase soil fertility by taking up nitrogen directly from the air.
c) Alcohol is made with yeast .
D. Cholera is caused by bacteria .
2. Mark '✓' the correct answer.
a) Yeast is used to produce sugar /alcohol / hydrochloric acid / oxygen.
Answer: Alcohol.
b) Sodium bicarbonate / streptomycin / alcohol / yeast is an antibiotic.
Answer: Streptomycin.
c) Female Enopheles mosquitoes / cockroaches / flies / butterflies / carriers of malaria-causing protozoa.
Answer: Female syphilis mosquito.
d) Insects / flies / ticks / spiders / carriers of infectious diseases.
Answer: Flies.
e) The load of bread or idli swells due to heat / grinding / growth of yeast cells / kneading of flour.
Answer: Enlargement of yeast cells.
f) The process of making alcohol from sugar is called nitrogen compounding / molding / fermentation / transfection.
Answer: Kinban.
3) Match the microorganisms in part 'A' with the action of part 'B' -
A | B |
i) Bacteria | a ) Nitrogen compounding |
ii) Rise ' Biam | b) In the manufacture of yogurt |
iii) Lacto ' bacillus | c) In the preparation of bread |
iv) East | d) In the pathogenesis of malaria |
v) Pro ' j ' wa | e) In the cause of cholera |
vi) Viruses | f) In the pathogenesis of AIDS |
| g) In the preparation of antibodies |
Answer:
A | B |
i) Bacteria | e) Occurrence of cholera |
ii) Rise ' Biam | a ) Nitrogen compounding |
iii) Lacto ' bacillus | b) In the manufacture of yogurt |
iv) East | c) In the preparation of bread |
v) Pro ' j ' wa | d) In the development of malaria |
vi) Viruses | f) In the pathogenesis of AIDS |
4) Can microorganisms be seen with the naked eye? How can they be seen?
A. Microorganisms are so tiny that they cannot be seen with the naked eye.
They can only be seen using high-powered fire glass or microscopes.
5. What are the major parts of microorganisms?
A. The major parts of microorganisms are -
bacteria , fungi , protozoa , and algae.
Viruses are intermediate between living and non-living things. It is inert in the normal environment but , behaves like an organism when in contact with an organism.
6. Name the microorganisms that can compound atmospheric nitrogen in soil.
A. Rhizobium and blue green algae.
7. Write 5 lines about the benefits of microorganisms in our lives.
A. Benefits of microorganisms:-
(i) Microorganisms decompose various organic wastes and increase soil fertility.
(ii) Lactobacillus converts milk into yogurt.
(iii) Bacteria are also used in the preparation of cheese, pickles and various food items.
(iv) Many microorganisms are also used in the production of liquor, wine, vinegar etc.
(v) Various microorganisms are also used to produce antibiotics.
8. Briefly write about the harms of microorganisms.
A. Microorganisms can cause damage in various ways. Some microorganisms cause disease in humans, plants and animals. Pathogenic microorganisms enter the body through breathing, drinking water or food and are transmitted from one person to another
Yes. In addition, microorganisms are one of the causes of diseases in plants like barley, rice, potatoes, oranges, apples etc. In addition, diseases such as anthrax in humans and cattle are also caused by the action of various microorganisms such as bacteria. Microorganisms can also cause food poisoning.
9. What are antibiotics? What precautions should I take when taking antibiotics?
A. Antibiotics are drugs that kill or inhibit the growth of disease-causing microorganisms.
Precautions:
i) Antibiotics should be taken only on the advice of a qualified doctor.
ii) Complete the course of medication as per the diagnosis given by the doctor.
iii) Unnecessary use of antibiotics is also harmful to health.
