Give examples to prove that microbes release gases during metabolism.
Solution and Explanation
(a) Bacteria and fungi carry out the process of fermination and during this process they release carbon dioxide. Fermination is the process of converting a complex organic substance into a simpler substance with the action of bacteria or yeast. Fermination of sugar produces alcohol with the release of carbon dioxide and very little energy.
Glucose→without oxygen alcohol+energy+CO2
(b) The dough used for making idli and dosa gives a puffed experience. This is because of the action of bacteria which releases carbon dioxide. This CO2 released from the dough gets trapped in the dough thereby giving it a puffed appearance.
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Concepts Used:
Microbes in Human Welfare
There are several valuable microorganisms that are beneficial to humans in various manners such as:
In Household Products
- Fermentation of milk to produce yogurt.
- Milk cuddling to compose curd, cheese, and paneer.
In Industrial Products
- Production of beverages such as wine, beer, whiskey, brandy, or rum.
- Production of antibiotics such as Penicillin and other chemical substances to kill or retard the expansion of disease-causing microbes.
Fermented Beverages
- A fermentor is used to produce microbes on a large scale for industrial purposes.
- The brewer’s yeast (Saccharomyces cerevisiae) is used to make ethanol. At this time, the yeast ferments malted cereals and fruit juices.
Antibiotics
- The term antibiotic means “against life”. These materials can kill or destroy the growth of other microbes.