Nutrient Cycles Flashcards
What are nutrient cycles?
Nutrient cycles are natural processes through which essential elements like carbon, nitrogen, and phosphorus are recycled in ecosystems.
What is the nitrogen cycle?
The nitrogen cycle is the process by which nitrogen is converted between its various chemical forms, including nitrogen gas, ammonia, nitrates, and proteins.
What is nitrogen fixation?
Nitrogen fixation is the process where nitrogen gas (N₂) is converted into ammonia (NH₃) by nitrogen-fixing bacteria, which can then be used by plants.
What is nitrification?
Nitrification is the process where ammonia is converted into nitrites (NO₂⁻) and then nitrates (NO₃⁻) by nitrifying bacteria, making nitrogen available for plants.
What is ammonification?
Ammonification is the conversion of organic nitrogen in dead organisms and waste into ammonia (NH₃) by decomposers.
What is denitrification?
Denitrification is the process where nitrates are converted back into nitrogen gas (N₂) by denitrifying bacteria, completing the nitrogen cycle.
What is the role of decomposers in nutrient cycling?
Decomposers break down dead organic matter and waste, releasing nutrients like nitrogen, carbon, and phosphorus back into the soil or atmosphere.
What is the carbon cycle?
The carbon cycle is the process by which carbon is exchanged between the atmosphere, oceans, soil, and living organisms, maintaining the balance of carbon on Earth.
How does carbon enter the atmosphere?
Carbon enters the atmosphere mainly through the process of respiration by organisms and combustion of fossil fuels.
How does carbon get absorbed by plants?
Carbon dioxide is absorbed by plants during photosynthesis, where it is used to produce glucose and other organic molecules.
What is the role of animals in the carbon cycle?
Animals contribute to the carbon cycle by respiring (releasing carbon dioxide), consuming plants (which contain carbon), and decomposing after death.
What is the role of the ocean in the carbon cycle?
Oceans absorb carbon dioxide from the atmosphere, and marine organisms play a role in storing carbon in the form of calcium carbonate (in shells and corals).
What is the phosphorus cycle?
The phosphorus cycle is the process by which phosphorus moves through the environment, including its movement from rocks to soil, plants, and organisms.
How does phosphorus enter the soil?
Phosphorus enters the soil primarily through the weathering of rocks, which releases phosphate ions that can be absorbed by plants.
How do plants and animals use phosphorus?
Plants absorb phosphate ions from the soil, and animals obtain phosphorus by consuming plants or other animals.
What happens to phosphorus when organisms die?
When organisms die, decomposers break down their bodies, releasing phosphorus back into the soil, where it can be absorbed by plants again.
What is the effect of human activity on nutrient cycles?
Human activities, such as agriculture and burning fossil fuels, can disrupt nutrient cycles by increasing nutrient runoff, pollution, and altering atmospheric gases.
