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Microbes in Human Welfare

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CBSE Gujarat Board Haryana Board

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Class 10 Class 12

Biochemical Oxygen Demand (BOD) in a river water

• remains unchanged when algal bloom occurs

• has no relationship with the concentration of oxygen in the water

• gives a measure of Salmonella in the water

• increases when sewage gets mixed with river water

D.

increases when sewage gets mixed with river water

Biochemical Oxygen Demand (BOD) is the amount of oxygen used for biochemical oxidation by micro-organisms in a unit volume of water. Polluted water has high BOD. Thus, when sewage gets mixed with river water, BOD will increase.

Biochemical Oxygen Demand (BOD) is the amount of oxygen used for biochemical oxidation by micro-organisms in a unit volume of water. Polluted water has high BOD. Thus, when sewage gets mixed with river water, BOD will increase.

585 Views

What is brewing ?

Brewing is a complex fermentation process, which involves the production of malt beverages such as beer, ale and stout. Saccharomyces cerevisiae is used for the process of fermentation.
587 Views

Name one micro-organism which is used in bakery.

Yeast .
622 Views

What is the difference between rum and whisky ?

Rum is obtained by the fermention of  sugarcane juice or molasses. It is fermented for a shorter period of time
while
whisky is obtained by fermentation of grains like wheat, corn,barley and rye. The fementation is done for a longer period of time.
681 Views

Which bacterium is responsible for the formation of curd from milk?

Lactobacillus  (Lactic acid bacteria).
2900 Views

Give the source of invertase enzyme (sucrase).

Saccharomyces cerevisiae
607 Views