Nitrogen Cycle MCQ Questions and Answers for Practice

1. Ammonification is the process of

1. Formation of ammonia from nitrates by nitrogen fixers
2. Formation of ammonia from nitrates by decomposers
3. Formation of ammonia from nitrogen by nitrogen fixers
4. Formation of ammonia from amino acids by decomposers

2. Nitrogen is assimilated/absorbed into plants in what form?

1. Nitrates
2. Both b and c
3. Nitrite
4. Ammonia

3. Only special bacteria can directly use nitrogen in our atmosphere and fix it so other organisms can benefit. These bacteria are called ....... bacteria

1. Nitrogen fixing
2. Nitrogen assimilation
3. Nitrogen making
4. Nitrogen adjusting

4. The conversion of Ammonia to Nitrite and then to Nitrates is called:

1. Nitrogen Fixation
2. deamination
3. Nitrification
4. Denitrification

5. The Haber process refers to which biogeochemical cycle?

1. Nitrogen
2. Water
3. Carbon
4. Sulfur

6. The nitrogen cycle is one of the most important and most complex of the biogeochemical cycles. It is important because nitrogen:

1. is a greenhouse gas
2. is the building-block of organic life
3. dilutes carbon dioxide and oxygen in the atmosphere
4. is an important nutrient, necessary for life

7. The nitrogen cycle, one of the most important biochemical cycles, may cause environmental problems because too much nitrogen can:

1. contribute to the greenhouse effect
2. cause eutrophication in bodies of water
3. result in acid rain
4. deplete the ozone layer

8. The process that converts Nitrates back to Nitrogen gas there by replenshing nitrogen in the atmosphere is called

1. Nitrogen Fixation
2. deamination
3. Nitrification
4. Denitrification

9. What is the most common way that nitrogen fixation occurs?

1. fossil fuel combustion
2. forest fires
3. lightning
4. nitrogen fixing bacteria

10. When incoming solar radiation is converted to heat, it is least likely to be trapped and reradiated as infrared radiation in the troposphere by

1. carbon dioxide
2. methane
3. nitrogen gas
4. water vapor