Presence of which pathogenic microbe in water is indication of contamination?

Question

Accepted Answer

Option 1, Coliform bacteria, is the correct answer because the presence of coliform bacteria in water is a well-established indicator of contamination, particularly by fecal matter. Coliform bacteria are a group of microorganisms commonly found in the intestines of warm-blooded animals, including humans. Their presence in water suggests that the water may be contaminated with pathogens that can cause diseases, such as E. coli, which is a specific type of coliform bacteria. Testing for coliform bacteria is a standard practice in water quality assessments to ensure the safety of drinking water.

Now, let's explain why the other options are incorrect:

2. Chlorella: Chlorella is a type of green algae, not a pathogenic microbe. It is often used as a dietary supplement due to its high nutrient content and is not associated with water contamination. Its presence in water does not indicate contamination by harmful pathogens.

3. Spirogyra: Spirogyra is another type of green algae, known for its spiral chloroplasts. Like Chlorella, Spirogyra is not pathogenic and does not indicate water contamination. It is commonly found in freshwater environments and is not harmful to human health.

4. Volvox: Volvox is a genus of green algae that forms spherical colonies. It is not a pathogenic microbe and does not serve as an indicator of water contamination. Volvox is typically found in clean, nutrient-rich waters and is not associated with health risks.

In summary, Option 1, Coliform bacteria, is the correct choice because it is a recognized indicator of water contamination, particularly by fecal matter, which can harbor harmful pathogens. The other options, being types of algae, do not indicate contamination and are not pathogenic.