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.
Top Questions on Microbes in human welfare
- Student to attempt either option (A) or (B): (A) Ravi lives in a village where he suggested to the local farmers to introduce a fungus as biofertilizer into their crop fields. State the benefits provided by the fungus to the crop.
OR
(B)- [(i)] How do secondary lymphoid organs provide immunity?
- [(ii)] Highlight the role of spleen as an organ that provides immunity.
- CBSE CLASS XII - 2025
- Biology
- Microbes in human welfare
- Assertion (A): Swiss cheese is characterized by large holes due to CO2 production.
Reason (R): It is ripened by growing a specific fungi.- CBSE CLASS XII - 2025
- Biology
- Microbes in human welfare
- Assertion (A): Swiss cheese is characterized by large holes due to CO2 production.
Reason (R): It is ripened by growing a specific fungi.- CBSE CLASS XII - 2025
- Biology
- Microbes in human welfare
- Large scale industrial production of streptokinase for human welfare is done using the microbe:
- CBSE CLASS XII - 2025
- Biology
- Microbes in human welfare
- Bottled fruit juices are clearer as compared to those made at home, as they are clarified by the use of:
- CBSE CLASS XII - 2025
- Biology
- Microbes in human welfare
Questions Asked in CBSE CLASS XII exam
- ‘But the game he is watching so intently is out of his reach.’ What are the factors that have made their game inaccessible to Saheb? (Lost Spring)
- CBSE CLASS XII - 2025
- Literature
- A charge \( -6 \mu C \) is placed at the center B of a semicircle of radius 5 cm, as shown in the figure. An equal and opposite charge is placed at point D at a distance of 10 cm from B. A charge \( +5 \mu C \) is moved from point ‘C’ to point ‘A’ along the circumference. Calculate the work done on the charge.
- CBSE CLASS XII - 2025
- Electrostatics
Which of the following is a better data story? Give reasons.
- CBSE CLASS XII - 2025
- data storytelling
How do good stories emerge?
- CBSE CLASS XII - 2025
- data storytelling
Match the following:
- CBSE CLASS XII - 2025
- data storytelling
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.