Q2 of 27 Page 1

The presence of a particular group of bacteria in water bodies indicates contamination. Identify the group.

The contamination of water bodies by human waste can be easily detected by the presence of coliform bacteria in the water bodies.

Explanation:


1. The large intestine of humans, as well as all the warm-blooded animals, usually contains certain bacteria’s like E. coli which when detected in water body indicate that the water body is polluted by the human waste.


2. Since these types of bacteria indicate the contamination of water bodies, these organisms are also referred to as indicator organisms.


3. It is not necessary that the indicator organisms are harmful to the health of humans, but their presence indicates poor quality of water in the water bodies.


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