What are microbes? Describe their role in human welfare in brief? Or, Discuss the role of Microbes, that are use as antibiotics.

Ans :--  Microbe is a minute life

form. Microbes are diverse-protozoa, bacteria, fungi and microscopic plants viruses, viroids and also prions that are proteinacious infectious agents.

Role of microbes in human welfare: --

From the moment of birth and 

throughout our entire lives, humans 

share a close relationship with a 

surprising variety of microscopic organisms. Microbes have played an important role in the preparation of household products. These are :---

House hold Products :---

1. Dairy Products :--- 

(i) Curd

(ii) Yoghurt

(iii) Butter milk

(iv) Cheese.

2. 'Dough' for making foods :----

Several food items such as 'dosa', 

'idli', 'jalebi' and 'bread' are prepared by fermentation process in which one or more kinds of microbes are used. These microbes are responsible for the typical flavour, texture and quality of the product.

3. Other household products:---

 Many other household products

 prepared as a result of microbial 

activity include Toddy', a traditional 

drink of some parts of southern India

is made by fermenting sap from palms; Microbes are also used to ferment fish, soyabean and bamboo-shoots to make foods.

Microbes in Industrial products :--

A variety of microbes are used to synthesize a number of industrial 

products valuable to human beings. Industrial production requires the

formation of large quantities of the produce, which normally involves the microbial reactions to proceed in a specialized vessel called fermentor 

of bioreactor. 

It is designed for large-scale industrial production of products. Beverages and antibiotics are some examples 1. Fermented Beverages, 2. Antibiotics.

Antibiotics :--  Antibiotics are

substances, primarily produced by

certain harmless microorganisms, 

which in low concentrations are antagonistic to the growth of other microorganisms such as pathogenic

 bacteria. There are several different classification systems for antibiotics, based on chemical structure, origin,

range or action. Some antibiotics are broad spectrum and can be used against

a wide variety of microorganisms, 

while others are very specific in their action and kill only microorganisms 

of one species or group. Selman

Waksman coined the term antibiotic

in 1942. Some common antibiotics 

and organisms producing them : --

(3.) Chemicals, Enzymes and other Bioactive Molecules :----

Quite a few chemicals like organic acids, alcohols and enzymes are industrially produced by the use of microbes. 

The main among them are :----

(i) Citric acid,

(ii) Acetic acid

(iii) Butyric acid

(iv) Ethanol 

(v) Lactic acid etc.