Biology · Microbes in Human Welfare · NEET
Microbes are found everywhere, not only in dirty places. NCERT clearly states microbes are present in soil, water, air, and inside the bodies of humans, animals and plants. Many of these microbes are useful or harmless. So the idea that microbes live only in dirt or waste is a wrong assumption that NEET likes to test.
Thermal vents (also called geysers) are hot springs where water temperature can be as high as 100C. Special microbes called extremophiles can live there. NCERT gives thermal vents as the classic example of a site where no other life form could survive, but microbes still grow. This shows microbes are the most widely spread group of living organisms.
It is the same idea, just different habitats. Soil holds a very large number and variety of microbes (bacteria, fungi, protozoa) and is the richest habitat. Water bodies also carry many microbes. Air mainly carries microbes as spores or droplets moving from place to place; it is a route of spread rather than a permanent home. For NEET, remember all three (soil, water, air) are listed together as common microbial habitats.
Yes. NCERT says microbes live inside the bodies of humans and other animals and plants. Many of these are normal residents (for example, gut microbes) and are not causing disease. So being a microbe does not mean being a pathogen; only some microbes cause disease.
In this NCERT chapter, the microbial world is described as diverse: protozoa, bacteria, fungi, and microscopic animal and plant viruses, viroids, and also prions (proteinaceous infectious agents). So when the chapter lists where microbes are found, it is talking about this whole diverse group, not bacteria alone.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
NCERT states microbes are present everywhere: in soil, water, air, inside the bodies of humans, and in other animals and plants. They also live in extreme sites such as thermal vents (up to 100C), deep in soil, under thick snow, and in highly acidic environments.
Thermal vents, also called geysers, are natural hot water sites where temperature can reach 100C. NCERT uses them as the example of a place where no other life could survive, yet microbes still grow there.
Soil is one of the richest microbial habitats, holding a huge number and variety of bacteria, fungi and protozoa. But NCERT lists soil, water and air together as the common places where microbes are found.
No. Many microbes inside our body are normal residents and are useful or harmless. Only some microbes cause disease. Being a microbe does not mean being a pathogen.
Yes, as a concept and trap-checker. NEET may test statements that wrongly limit where microbes live. Knowing that microbes are found almost everywhere, including extreme environments, helps you reject 'only' type wrong options.
