NEET Biology: Biology - Environmental Biology questions with solutions

Q1. Which one of the following statements is correct?

1. At present it is not possible to grow maize without chemical fertilizers.
2. Extensive use of chemical fertilizer may lead to eutrophication of nearby water bodies.
3. Both Azotobacter and Rhizobium fix atmospheric nitrogen in root nodules of plants.
4. Cyanobacteria such as Anabaena and Nostoc are important mobilizers of phosphates and potassium for plant nutrition in the soil.

Answer: Extensive use of chemical fertilizer may lead to eutrophication of nearby water bodies.

Excess chemical fertilizers can be carried by rainwater into nearby water bodies, adding too much nitrogen and phosphorus. This nutrient overload promotes algal blooms and oxygen depletion, which is eutrophication.

Q2. What are the chief pollutants of the atmosphere, which are most likely to deplete the ozone layer?

1. Sulphur dioxide
2. Nitrogen oxide and Fluorocarbons
3. Carbon dioxide
4. Carbon monoxide

Answer: Nitrogen oxide and Fluorocarbons

Nitrogen oxides and fluorocarbons are major ozone-depleting pollutants because they participate in reactions that break down ozone molecules in the stratosphere. The other options are important air pollutants, but they are not the chief causes of ozone layer depletion.