Question 2

Tick the correct answer:

(a) Yeast is used in the production of
(i) sugar (ii) alcohol (iii) hydrochloric acid (iv) oxygen

(b) The following is an antibiotic
(i) Sodium bicarbonate (ii) Streptomycin (iii) Alcohol (iv) Yeast

(c) Carrier of malaria-causing protozoan is
(i) female Anopheles mosquito (ii) cockroach (iii) housefly (iv) butterfly

(d) The most common carrier of communicable diseases is
(i) ant (ii) housefly (iii) dragonfly (iv) spider

(e) The bread or idli dough rises because of
(i) heat (ii) grinding (iii) growth of yeast cells (iv) kneading

(f) The process of conversion of sugar into alcohol is called
(i) nitrogen fixation (ii) moulding (iii) fermentation (iv) infection

Answer

(a) (ii) Alcohol

Yeast is used in the production of alcohol. This process is known as fermentation.

(b) (ii) Streptomycin

Streptomycin is an antibiotic, it is used to relieve the pain and kills other disease causing microorganisms.

Malaria is caused by a mosquito. The carrier of Malaria causing protozoan is Female Anopheles mosquito.

(d) (ii) Housefly

The most common carrier of communicable disease is housefly. It spreads the disease causing microorganisms.

(e) (iii) Growth of yeast cells

This process is called as fermentation. The dough rises due to the increased growth of yeast cells.

(f) (iii) Fermentation

The conversion of sugar into alcohol with the help of yeast cells is called as fermentation.

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