BIOLOGY IN HUMAN WELFARE
MICROBES IN HUMAN WELFARE
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
That water is pure
|
|
|
that water is less polluted
|
|
|
that water is highly polluted
|
|
|
that consumption of organic matter by microbes is higher in the water
|
Detailed explanation-1: -BOD indicates the amount of organic matter present in water. Therefore, a low BOD is an indicator of good quality water, while a high BOD indicates polluted water. Dissolved oxygen (DO) is consumed by bacteria when large amounts of organic matter from sewage or other discharges are present in the water.
Detailed explanation-2: -Higher BOD indicates more oxygen is required, which is less for oxygen-demanding species to feed on, and signifies lower water quality. Inversely, low BOD means less oxygen is being removed from water, so water is generally purer.
Detailed explanation-3: -High value of BOD (Biochemical Oxygen Demand) indicates that water is highly polluted.
Detailed explanation-4: -BOD (Biological Oxygen Demand) is less than 5ppm in clean water, where as highly polluted water have a BOD value of 17ppm are more.
Detailed explanation-5: -BOD is a measure of the amount of oxygen required to remove waste organic matter from water in the process of decomposition by aerobic bacteria (those bacteria that live only in an environment containing oxygen).