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455 questions in this collection · Page 1 of 46
Question 1 of 455
📘 CLASS XII
Microbes In Human Welfare
Microbes are present everywhere, including extreme sites like deep inside geysers where the temperature may be as high as:
Microbes are present even at sites where no other life-form could possibly exist, such as deep inside the geysers (thermal vents) where the temperature may be as high as 100°C.
Question 2 of 455
📘 CLASS XII
Microbes In Human Welfare
Which of the following is an example of a proteinaceous infectious agent mentioned among microbes?
Microbes are diverse, including protozoa, bacteria, fungi, viruses, viroids, and also prions that are proteinacious infectious agents.
Question 3 of 455
📘 CLASS XII
Microbes In Human Welfare
Microbes like bacteria and many fungi can be grown on nutritive media to form visible masses called:
Microbes like bacteria and many fungi can be grown on nutritive media to form colonies that can be seen with the naked eyes.
Question 4 of 455
📘 CLASS XII
Microbes In Human Welfare
What is the common term used for micro-organisms such as Lactobacillus that convert milk to curd?
Micro-organisms such as Lactobacillus and others are commonly called lactic acid bacteria (LAB) and grow in milk, converting it to curd.
Question 5 of 455
📘 CLASS XII
Microbes In Human Welfare
The conversion of milk to curd by LAB improves its nutritional quality primarily by increasing the content of which vitamin?
LAB convert milk to curd, which also improves its nutritional quality by increasing vitamin B 12.
Question 6 of 455
📘 CLASS XII
Microbes In Human Welfare
The puffed-up appearance of dough used for making foods like dosa and idli is primarily due to the production of which gas?
The puffed-up appearance of dough is due to the production of CO2 gas during fermentation by bacteria.
Question 7 of 455
📘 CLASS XII
Microbes In Human Welfare
Which species of yeast is commonly used for fermenting the dough used for making bread, and is also called baker’s yeast?
The dough for making bread is fermented using baker’s yeast (Saccharomyces cerevisiae).
Question 8 of 455
📘 CLASS XII
Microbes In Human Welfare
The traditional drink ‘Toddy’ from southern India is prepared by fermenting the sap from which source?
‘Toddy’, a traditional drink of some parts of southern India, is made by fermenting sap from palms.
Question 9 of 455
📘 CLASS XII
Microbes In Human Welfare
The large holes characteristic of Swiss cheese are caused by the production of a large amount of CO2 by the bacterium named:
The large holes in “Swiss cheese” are due to production of a large amount of CO2 by a bacterium named Propionibacterium sharmanii.
Question 10 of 455
📘 CLASS XII
Microbes In Human Welfare
The large holes characteristic of Swiss cheese are caused by the production of a large amount of CO2 by the bacterium named:
The large holes in ‘Swiss cheese’ are due to production of a large amount of CO2 by a bacterium named Propionibacterium sharmanii.