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Which of the following is an example of human-induced nitrogen fixation?- a)Nitrogen fixation by leguminous plants
- b)Nitrogen fixation by lightning
- c)Nitrogen fixation by nitrogen-fixing bacteria
- d)Nitrogen fixation by volcanic eruptions
Correct answer is option 'C'. Can you explain this answer?
Which of the following is an example of human-induced nitrogen fixation?
a)
Nitrogen fixation by leguminous plants
b)
Nitrogen fixation by lightning
c)
Nitrogen fixation by nitrogen-fixing bacteria
d)
Nitrogen fixation by volcanic eruptions
|
Jaya Chopra answered |
Human-induced nitrogen fixation:
Nitrogen fixation is the process by which atmospheric nitrogen is converted into a form that plants can use for growth. While natural sources of nitrogen fixation include lightning and nitrogen-fixing bacteria, human activities also play a significant role in this process.
Nitrogen fixation by nitrogen-fixing bacteria:
One of the most common examples of human-induced nitrogen fixation is the use of nitrogen-fixing bacteria in agriculture. Farmers often add nitrogen-fixing bacteria to the soil to increase nitrogen availability for crops. These bacteria form symbiotic relationships with leguminous plants, such as peas and beans, and help convert atmospheric nitrogen into a form that the plants can use.
Impact of human-induced nitrogen fixation:
- Human-induced nitrogen fixation has significantly increased the amount of nitrogen available for plant growth, leading to higher crop yields.
- However, excessive use of nitrogen-fixing bacteria and other nitrogen fertilizers can also have negative impacts on the environment, such as pollution of water bodies and soil degradation.
In conclusion, nitrogen fixation by nitrogen-fixing bacteria in agriculture is an example of human-induced nitrogen fixation. This practice has both positive and negative impacts on the environment, highlighting the importance of sustainable agricultural practices.
Nitrogen fixation is the process by which atmospheric nitrogen is converted into a form that plants can use for growth. While natural sources of nitrogen fixation include lightning and nitrogen-fixing bacteria, human activities also play a significant role in this process.
Nitrogen fixation by nitrogen-fixing bacteria:
One of the most common examples of human-induced nitrogen fixation is the use of nitrogen-fixing bacteria in agriculture. Farmers often add nitrogen-fixing bacteria to the soil to increase nitrogen availability for crops. These bacteria form symbiotic relationships with leguminous plants, such as peas and beans, and help convert atmospheric nitrogen into a form that the plants can use.
Impact of human-induced nitrogen fixation:
- Human-induced nitrogen fixation has significantly increased the amount of nitrogen available for plant growth, leading to higher crop yields.
- However, excessive use of nitrogen-fixing bacteria and other nitrogen fertilizers can also have negative impacts on the environment, such as pollution of water bodies and soil degradation.
In conclusion, nitrogen fixation by nitrogen-fixing bacteria in agriculture is an example of human-induced nitrogen fixation. This practice has both positive and negative impacts on the environment, highlighting the importance of sustainable agricultural practices.
Which of the following is an example of a natural nitrogen-fixing plant?- a)Wheat
- b)Corn
- c)Soybeans
- d)Rice
Correct answer is option 'C'. Can you explain this answer?
Which of the following is an example of a natural nitrogen-fixing plant?
a)
Wheat
b)
Corn
c)
Soybeans
d)
Rice
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Knowledge Hub answered |
An example of a natural nitrogen-fixing plant is soybeans (Option C). Leguminous plants, including soybeans, have a symbiotic relationship with nitrogen-fixing bacteria, such as Rhizobium, which enables them to fix atmospheric nitrogen and convert it into forms that can be used by the plants.
How does excess nitrogen in aquatic ecosystems negatively impact the environment?- a)It promotes excessive plant growth.
- b)It reduces oxygen levels in the water.
- c)It increases biodiversity.
- d)It enhances the survival of fish species.
Correct answer is option 'A'. Can you explain this answer?
How does excess nitrogen in aquatic ecosystems negatively impact the environment?
a)
It promotes excessive plant growth.
b)
It reduces oxygen levels in the water.
c)
It increases biodiversity.
d)
It enhances the survival of fish species.
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Knowledge Center answered |
Excess nitrogen in aquatic ecosystems negatively impacts the environment by promoting excessive plant growth (Option A). This leads to algal blooms, which can deplete oxygen levels in the water when the algae die and decompose. The reduced oxygen levels can harm other aquatic organisms and disrupt the ecosystem balance.
Which of the following is an example of a symbiotic relationship in the nitrogen cycle?- a)Ammonification and nitrification
- b)Nitrification and denitrification
- c)Nitrogen fixation and assimilation
- d)Nitrosomonas and plants
Correct answer is option 'C'. Can you explain this answer?
Which of the following is an example of a symbiotic relationship in the nitrogen cycle?
a)
Ammonification and nitrification
b)
Nitrification and denitrification
c)
Nitrogen fixation and assimilation
d)
Nitrosomonas and plants
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|
Knowledge Hub answered |
An example of a symbiotic relationship in the nitrogen cycle is Nitrogen fixation and assimilation (Option C). Nitrogen fixation is the process of converting atmospheric nitrogen into a usable form, while assimilation refers to the incorporation of nitrogen into organic compounds by plants and other organisms.
What is the significance of the nitrogen cycle in agriculture?- a)It reduces the need for fertilizers.
- b)It increases the yield of crops.
- c)It decreases soil erosion.
- d)It improves water quality.
Correct answer is option 'B'. Can you explain this answer?
What is the significance of the nitrogen cycle in agriculture?
a)
It reduces the need for fertilizers.
b)
It increases the yield of crops.
c)
It decreases soil erosion.
d)
It improves water quality.
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|
Knowledge Hub answered |
The significance of the nitrogen cycle in agriculture is that it increases the yield of crops (Option B). Nitrogen is an essential nutrient for plant growth, and the availability of nitrogen through the nitrogen cycle supports healthy plant development, leading to increased agricultural productivity.
What is the primary cause of nitrogen pollution?- a)Industrial emissions
- b)Deforestation
- c)Volcanic activity
- d)Agricultural runoff
Correct answer is option 'D'. Can you explain this answer?
What is the primary cause of nitrogen pollution?
a)
Industrial emissions
b)
Deforestation
c)
Volcanic activity
d)
Agricultural runoff
|
|
Knowledge Center answered |
The primary cause of nitrogen pollution is agricultural runoff (Option D). Excess nitrogen from fertilizers and animal waste used in agriculture can be washed into water bodies through runoff, leading to water pollution and ecosystem disruption.
What is the role of lightning in the nitrogen cycle?- a)It converts atmospheric nitrogen into nitrates.
- b)It releases nitrogen gas into the atmosphere.
- c)It increases the concentration of ammonia in the soil.
- d)It enhances the process of nitrogen assimilation.
Correct answer is option 'A'. Can you explain this answer?
What is the role of lightning in the nitrogen cycle?
a)
It converts atmospheric nitrogen into nitrates.
b)
It releases nitrogen gas into the atmosphere.
c)
It increases the concentration of ammonia in the soil.
d)
It enhances the process of nitrogen assimilation.
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|
Knowledge Center answered |
Lightning contributes to the nitrogen cycle by converting atmospheric nitrogen into nitrates (Option A). During a lightning strike, the high temperature and energy cause the nitrogen gas in the atmosphere to react with oxygen, forming nitrogen oxides that eventually dissolve in rainwater to form nitrates.
What is the role of plants in the nitrogen cycle?- a)They fix nitrogen from the atmosphere.
- b)They release nitrogen gas.
- c)They convert nitrogen gas into nitrates.
- d)They decompose organic matter.
Correct answer is option 'A'. Can you explain this answer?
What is the role of plants in the nitrogen cycle?
a)
They fix nitrogen from the atmosphere.
b)
They release nitrogen gas.
c)
They convert nitrogen gas into nitrates.
d)
They decompose organic matter.
|
|
Knowledge Hub answered |
Plants play a crucial role in the nitrogen cycle as they fix nitrogen from the atmosphere (Option A). Through symbiotic relationships with nitrogen-fixing bacteria or through their own root nodules, certain plants have the ability to convert atmospheric nitrogen into forms that can be utilized by other organisms in the ecosystem.
Which process releases nitrogen gas into the atmosphere?- a)Volcanic activity
- b)Photosynthesis
- c)Combustion
- d)Sedimentation
Correct answer is option 'C'. Can you explain this answer?
Which process releases nitrogen gas into the atmosphere?
a)
Volcanic activity
b)
Photosynthesis
c)
Combustion
d)
Sedimentation
|
|
Knowledge Hub answered |
Combustion (Option C) is the process that releases nitrogen gas into the atmosphere. When organic matter, such as fossil fuels or biomass, is burned, nitrogen present in the material is released as nitrogen gas.
Which of the following is NOT a step in the nitrogen cycle?- a)Nitrogen fixation
- b)Nitrification
- c)Decomposition
- d)Transpiration
Correct answer is option 'D'. Can you explain this answer?
Which of the following is NOT a step in the nitrogen cycle?
a)
Nitrogen fixation
b)
Nitrification
c)
Decomposition
d)
Transpiration
|
|
Knowledge Center answered |
Transpiration (Option D) is not a step in the nitrogen cycle. Transpiration refers to the process by which plants release water vapor from their leaves into the atmosphere.
What type of bacteria is responsible for nitrogen fixation?- a)Nitrosomonas
- b)Nitrobacter
- c)Rhizobium
- d)Pseudomonas
Correct answer is option 'C'. Can you explain this answer?
What type of bacteria is responsible for nitrogen fixation?
a)
Nitrosomonas
b)
Nitrobacter
c)
Rhizobium
d)
Pseudomonas
|
|
Knowledge Center answered |
The bacteria responsible for nitrogen fixation is Rhizobium (Option C). Rhizobium forms a symbiotic relationship with leguminous plants, such as soybeans and clover, and resides in their root nodules. These bacteria have the enzyme nitrogenase, which enables them to convert atmospheric nitrogen into ammonia, benefiting both the bacteria and the plants.
What is the main source of nitrogen for the nitrogen cycle?- a)Atmosphere
- b)Rocks and minerals
- c)Fertilizers
- d)Water bodies
Correct answer is option 'A'. Can you explain this answer?
What is the main source of nitrogen for the nitrogen cycle?
a)
Atmosphere
b)
Rocks and minerals
c)
Fertilizers
d)
Water bodies
|
|
Knowledge Center answered |
The main source of nitrogen for the nitrogen cycle is the atmosphere (Option A). The Earth's atmosphere is composed of approximately 78% nitrogen gas (N2), making it the largest reservoir of nitrogen.
What is the consequence of eutrophication caused by excessive nitrogen in water bodies?- a)Decreased algal blooms
- b)Improved water clarity
- c)Oxygen depletion and fish kills
- d)Reduced nutrient availability
Correct answer is option 'C'. Can you explain this answer?
What is the consequence of eutrophication caused by excessive nitrogen in water bodies?
a)
Decreased algal blooms
b)
Improved water clarity
c)
Oxygen depletion and fish kills
d)
Reduced nutrient availability
|
|
Knowledge Hub answered |
The consequence of eutrophication caused by excessive nitrogen in water bodies is oxygen depletion and fish kills (Option C). When excess nitrogen enters water bodies, it promotes the growth of algae and other aquatic plants. As these organisms die and decompose, the process consumes oxygen, leading to hypoxia (low oxygen levels) or anoxia (no oxygen) in the water, which can result in fish and other aquatic organism deaths.
Which human activity has disrupted the nitrogen cycle by increasing the amount of nitrogen in the environment?- a)Deforestation
- b)Agricultural practices
- c)Recycling
- d)Water conservation
Correct answer is option 'B'. Can you explain this answer?
Which human activity has disrupted the nitrogen cycle by increasing the amount of nitrogen in the environment?
a)
Deforestation
b)
Agricultural practices
c)
Recycling
d)
Water conservation
|
|
Knowledge Center answered |
The human activity that has disrupted the nitrogen cycle by increasing the amount of nitrogen in the environment is agricultural practices (Option B). The use of synthetic fertilizers in agriculture, as well as the rearing of livestock, has led to increased nitrogen runoff into water bodies and nitrogen deposition in ecosystems, causing environmental issues such as eutrophication and water pollution.
How does nitrogen affect the pH of soil?- a)It decreases soil acidity.
- b)It increases soil alkalinity.
- c)It has no impact on soil pH.
- d)It varies depending on the nitrogen compound.
Correct answer is option 'D'. Can you explain this answer?
How does nitrogen affect the pH of soil?
a)
It decreases soil acidity.
b)
It increases soil alkalinity.
c)
It has no impact on soil pH.
d)
It varies depending on the nitrogen compound.
|
|
Knowledge Center answered |
The impact of nitrogen on soil pH varies depending on the nitrogen compound (Option D). Ammonium-based fertilizers can decrease soil pH, making it more acidic, while nitrates can have a neutral or slightly alkaline effect on soil pH.
What is the role of denitrifying bacteria in the nitrogen cycle?- a)Convert nitrate to nitrite
- b)Convert ammonium to nitrate
- c)Convert nitrate to nitrogen gas
- d)Convert nitrogen gas to nitrate
Correct answer is option 'C'. Can you explain this answer?
What is the role of denitrifying bacteria in the nitrogen cycle?
a)
Convert nitrate to nitrite
b)
Convert ammonium to nitrate
c)
Convert nitrate to nitrogen gas
d)
Convert nitrogen gas to nitrate
|
|
Knowledge Center answered |
The role of denitrifying bacteria in the nitrogen cycle is to convert nitrate to nitrogen gas (Option C). These bacteria carry out denitrification, breaking down nitrate and releasing nitrogen gas back into the atmosphere.
In which form is nitrogen primarily absorbed by plants?- a)Nitrate (NO3-)
- b)Nitrite (NO2-)
- c)Ammonium (NH4+)
- d)Nitrogen gas (N2)
Correct answer is option 'A'. Can you explain this answer?
In which form is nitrogen primarily absorbed by plants?
a)
Nitrate (NO3-)
b)
Nitrite (NO2-)
c)
Ammonium (NH4+)
d)
Nitrogen gas (N2)
|
|
Knowledge Center answered |
Plants primarily absorb nitrogen in the form of nitrate (NO3-) (Option A). Nitrate is the most common form of nitrogen taken up by plant roots from the soil.
How does nitrogen become available to animals in the food chain?- a)They directly absorb nitrogen from the atmosphere.
- b)They consume plants or other animals that contain nitrogen.
- c)They synthesize nitrogen from sunlight.
- d)They obtain nitrogen from water sources.
Correct answer is option 'B'. Can you explain this answer?
How does nitrogen become available to animals in the food chain?
a)
They directly absorb nitrogen from the atmosphere.
b)
They consume plants or other animals that contain nitrogen.
c)
They synthesize nitrogen from sunlight.
d)
They obtain nitrogen from water sources.
|
|
Knowledge Center answered |
Animals obtain nitrogen in the food chain by consuming plants or other animals that contain nitrogen (Option B). Nitrogen is an essential component of proteins and other biomolecules, and animals obtain it through their diet.
Which process converts atmospheric nitrogen into a form usable by plants?- a)Nitrogen fixation
- b)Nitrification
- c)Denitrification
- d)Ammonification
Correct answer is option 'A'. Can you explain this answer?
Which process converts atmospheric nitrogen into a form usable by plants?
a)
Nitrogen fixation
b)
Nitrification
c)
Denitrification
d)
Ammonification
|
|
Knowledge Center answered |
The process that converts atmospheric nitrogen into a form usable by plants is nitrogen fixation (Option A). Nitrogen fixation is carried out by certain types of bacteria, which have the ability to convert atmospheric nitrogen into ammonia (NH3) or ammonium (NH4+), which can be taken up by plants.
Which process returns nitrogen back to the atmosphere?- a)Denitrification
- b)Nitrogen fixation
- c)Nitrification
- d)Assimilation
Correct answer is option 'A'. Can you explain this answer?
Which process returns nitrogen back to the atmosphere?
a)
Denitrification
b)
Nitrogen fixation
c)
Nitrification
d)
Assimilation
|
|
Knowledge Center answered |
The process that returns nitrogen back to the atmosphere is denitrification (Option A). Denitrifying bacteria convert nitrate (NO3-) back into nitrogen gas (N2), completing the nitrogen cycle and releasing nitrogen back into the atmosphere.
Chapter doubts & questions for Nitrogen Cycle - Lucent for GK 2025 is part of UPSC CSE exam preparation. The chapters have been prepared according to the UPSC CSE exam syllabus. The Chapter doubts & questions, notes, tests & MCQs are made for UPSC CSE 2025 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests here.
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