NCERT textbooks describe microbes as single-celled organisms like bacteria and fungi. These organisms are microscopic. While they are often linked to dirt, microorganisms also have certain benefits. 

For example, they contribute to keeping nature clean. Microbes help in ensuring clean water in aquaculture. Microbial cells are another term for microbes or microorganisms. These terms can be used interchangeably.

The Class 12 textbook further explains in this chapter that microbes exist everywhere. They are in the soil, water, the air we breathe, etc. Microbes are also present in places where there is no evidence of life. Microbes have several uses in households. They are present in edible mushrooms, which are cultivated almost everywhere. 

One of the most popular microbial cells which are frequently used in homes is yeast. Yeast is a frequently used ingredient in food production, especially while baking breads and other doughs. The preparation of dairy products such as cheese and yoghurt also involves the cultivation of bacteria that help this process. 

In the context of Indian food, microorganisms come into play while cooking foods such as idli and dosa. The batter used for these food items needs to be fermented before it can be cooked. Fermentation is described as the process by which edible substances are broken down by microorganisms to produce carbon dioxide, which helps the dough to rise and causes its fluffiness. 

Some other foods produced via fermentation include Tofu, a Japanese bean curd made from soy milk. The Indonesian food Tempeh is also made using fermented soybeans. The production of dairy products like sour cream and curd also requires microbes like bacteria.

On the industrial front, microbes are used to produce ethanol, which is used as a fuel and solvent in several processes. Microbes are also used in a process known as bioleaching, which involves the extraction of metals from low ores. These metals cannot be extracted by using the usual chemical processes. Copper and uranium are two popular metals that are extracted through bioleaching. Listed below are some more functions of these microorganisms in industries. 

• Glycerol, which is often used in the food and medicine industry is produced through microbial interactions 
• Mannitol, which is used in the medicine industry and for research purposes is a sugar alcohol produced by microbes. 
• Butanol, which is used in the production of explosives, is also produced in a similar manner 
• Microbes are used in recombinant DNA. This is a process that allows the insertion of a general human gene into a bacterial substance. The newly created microorganism can produce the protein contained in the human gene. Recombinant DNA helped in the process of insulin during early times. Insulin is a hormone that helps regulate glucose (sugar) and is needed by the body for other body functions. Human insulin is grown inside bacteria. Yeast is also used for this purpose. The protein inside the human body that helps produce insulin is needed for research.

The Class 12 chapter Microbes In Human Welfare also discusses the importance of microbes for biocontrol. Biocontrol is the process of using biological methods to control pests and plant-related diseases. Pesticides and other chemical substances are very harmful to the environment and human beings. Natural methods are eco-friendly and don't harm the environment. Microbes are used in the production of biopesticides, which are used in the eradication of weeds, insects, and pathogens. These pesticides have many kinds of plants, animals, bacteria, fungi, etc. Some uses of microbial biocontrol agents have been listed below:

1. Bacterial pesticides – A subspecies of Bacillus Thuringiensis is mainly used for these kinds of pesticides. The dried spore of Bacillus Thuringiensis is mixed with water and is used as a pesticide for fruit-growing trees. 

2. Fungal pesticides – Beauveria bassiana is a fungus that causes white muscardine disease in insects, and is used as an insecticide.

Using microbes as bio controllers comes with multiple benefits. Some of these benefits are as follows: 

1. They are very pocket-friendly.

2. They are eco-friendly and do not harm the surroundings.

The chapter on microbes in human welfare also elaborates on the use of microbes in fertilisers to increase the availability of nutrients to crops. This happens both directly and indirectly. Microbes are used for crop enrichment. Usage of these organisms in the form of fertilisers is very environment friendly and also environmentally sustainable. Microbes to be used as fertilisers are developed under scientific supervision and are provided to farmers for use. Bacteria, fungi, and another microbe known as cyanobacteria are the three microorganisms used to develop biofertilizers. 

There are numerous advantages of using microbes in biofertilizers. These include:

1. They are easy to use.

2. Biofertilizers are naturally capable of increasing the nitrogen content in crops.

3. Microbes do not cause soil pollution.

4. They are pocket-friendly when compared with chemical fertilisers. 

5. They help in ensuring soil fertility.

The fertilisers which use microbes that have been discussed in the Ncert Class 12 chapter Microbes in human welfare are:

1. Nostoc - Nostoc is a type of cyanobacteria that fills nitrogen in plants and crops. 

2. Azotobacter - It is a type of bacteria found in some alkaline soils. 

3. Rhizobium - This is a type of bacteria that helps increase crop yield.

The chapter Microbes In Human Welfare Class 12 concludes effectively that Microbes are single-celled organisms present everywhere. These organisms are found in the human body, in water, and are part of several aspects of our daily life. 

Some types of microbes are harmful to the health of animals and human beings and are capable of causing severe damage to them. There are several bacteria, fungi, and viruses that are responsible for causing ill effects on animals and humans. 

However, there also exist many microorganisms that are beneficial to us. One of the many significant uses of microbes is the creation of human insulin. Many household and dairy products are processed from bacteria and yeast. The process of fermentation also revolves solely around microbial activity. Microbes have an essential industrial usage too. Bioleaching has effective results because of using microorganisms to extract metals. They are also used as biocontrollers and biofertilizers.

Q. Why are these notes of Microbes In Human Welfare Class 12 beneficial? 

A. The Ncert chapter Microbes In Human Welfare is an interesting and intriguing one. It contains a definite clarification of the subject. Whenever tests are overhauled, going through extensive texts is tough. Microbes In Human Welfare Ncert Solutions prove useful at such a period. These notes are made ready by exceptionally equipped instructors and are useful for giving examinations

Q. Will Microbes In Human Welfare Class 12 be necessary for attempting the NEET exam?

A. Studying microbes is useful since they have a role in several household processes, industries, and cycles for human advantage. Meanwhile, the chapter Microbes in Human Welfare also has a few significant topics which are frequently asked in NEET assessments. Consequently, students ought to remember this part well as it can help them achieve high scores in the competitive exam. 

Q. What is the role of microbes in checking disease-causing organism growth in the stomach? 

A. Lactic acid bacteria helps in controlling the development of infection-causing microorganisms in our stomach. It works by restraining the development of waste specialists. These are the microbes responsible for transforming milk into yoghurt. 

Q. How do microbes obtain nutrients for their growth? 

A. From what we have studied so far in the Microbes In Human Welfare Class 12 NCERT Solutions, we got to know that the microbes may perform photosynthesis by being autotrophic, or they may obtain their nutrients in a heterotrophic way, i.e., from surrounding cultures of sugar, water, carbon, and also dead and decaying plant and animal matter.