Ans. Food poisoning could be due to the consumption of food spoilt by some microorganisms.
Ans. We add salt or acid preservatives to pickles to prevent the attack of microbes.
Ans. Chemicals (Salts, edible oils etc.) used to check the growths of microorganisms are called preservatives.
Ans. Pasteurized milk can be consumed without boiling as it is free from harmful microbes.
Ans. Unicellular organisms- bacteria, some algae and protozoa
Multicellular organisms- algae and fungi
Ans. We prevent the spread of communicable diseases:
i. By keeping handkerchief on the nose and mouth while sneezing.
ii. By keeping distance from infected persons.
Ans. Viruses are quite different from other microorganisms. They reproduce only inside the host organism; bacterium, plant or animal cell.
Ans. Some microorganisms decompose the organic waste and dead plants and animals into simple substances and clean up the environment.
Ans. Sodium benzoate and sodium metabisulphite are used in the jams and squashes to check their spoilage.
Ans. Microorganisms are classified into four major groups. These groups are bacteria, fungi, protozoa and some algae.
Ans. Microorganisms or microbes are the living organisms around us which cannot be seen with naked eye.
Ans. Several diseases, including cholera, tuberculosis, smallpox and hepatitis can be prevented by vaccination.
Ans. We keep food in the refrigerator because low temperature inhibits the growth of microbes and keep the food fresh.
Ans. Dry fruits and even vegetables are sold in sealed air tight packets to prevent the attack of microbes.
Ans. It is important to vaccinate small children in order to protect them against several diseases.
Ans. Robert Köch (1876) discovered the bacterium (Bacillus anthracis) which causes anthrax disease.
Ans. Cholera is transmitted through water or food.
Typhoid is transmitted through water.
Ans. Anthrax is a dangerous cattle disease caused by a bacterium.
Foot and mouth disease of cattle is caused by a virus.