How has the discovery of antibiotics helped mankind in the field of medicine?
Antibiotics produced by microbes are regarded as one of the most significant discoveries of the twentieth century and have greatly contributed towards the welfare of the human society.
Anti is a Gk. word that means 'against' and bio means 'life', together they mean 'against life' (in the context of disease causing organisms); whereas with reference to human beings, they are 'pro life' and not against. Antibiotics are chemical substances, which are produced by some microbes and can kill or retard the growth of other (disease-causing) microbes.
Antibiotics have greatly improved our capacity to treat deadly diseases such as plague, whooping cough (Kali khansi), diphtheria (Gal ghotu) and leprosy (Kusht rog), which had killed millions all over the globe. Today, we can not imagine a world without antibiotics.
Why is distillation required for producing certain alcoholic drinks?
Depending on the type of the raw material used for fermentation and the type of processing (with or without distillation) different types of alcoholic drinks are obtained.
Wine and beer are produced without distillation whereas whiskey, brandy and rum are produced by distillation of the fermented broth.
Distillation increases the alcohol content in alcoholic drinks. That's why for producing certain alcoholic drinks, distillation is required.
Write the most important characteristic that Aspergillus niger, Clostridium butylicum, and Lactobacillus share.
Their common characteristic is that they produce organic acids as part of their metabolism and are therefore, used for commercial and industrial production of the same.
(i) Aspergillus niger (a fungus) for citric acid.
(ii) Clostridium butylicum (a bacterium) for butyric acid.
(iii) Lactobacillus (a bacterium) for lactic acid.
What would happen if our intestine harbours microbial flora exactly similar to that found in the rumen of cattle?
If our intestine harbors microbial flora exactly similar to that found in the rumen of cattle, we would be able to digest the cellulose present in our foods because the microbes present in the rumen (a part of stomach) of cattle, collectively called methanogens, are capable of digesting cellulose as they have cellulase enzyme.
Give any two microbes that are useful in biotechnology.
Two microbes that are useful in biotechnology are
(i) Bacillus thuringiensis a gene isolated from this bacterium is introduced in cotton plants to make them able to kill butterfly caterpillars.
(ii) Escherichia coli is a bacterium that is used in many biotechnology procedures. Their plasmid is used as vector to introduce foreign DNA segment in desired organisms.