Nutrient cycles：练习题

In the carbon cycle, which process is responsible for removing carbon dioxide from the atmosphere to form organic compounds like glucose?

In the nitrogen cycle, which group of microorganisms is responsible for the conversion of ammonium ions into nitrate ions in the soil?

Which statement correctly identifies a fundamental similarity between the carbon cycle and the nitrogen cycle?

In the nitrogen cycle, which process involves the conversion of nitrate ions into nitrogen gas?

In the carbon cycle, which process is the only one that directly results in a decrease in the concentration of carbon dioxide \( (CO_2) \) in the atmosphere?

Describe the role of nitrifying bacteria in the nitrogen cycle and explain why their activity is essential for the production of plant proteins after the decomposition of organic matter.

Explain how the processes of photosynthesis, respiration, and combustion interact to maintain the balance of carbon dioxide in the atmosphere within the carbon cycle.

Describe the specific role of denitrifying bacteria in the nitrogen cycle and identify the environmental conditions, such as those found in waterlogged soil, that promote their activity.

Nitrogen is essential for the synthesis of proteins in all living organisms. However, most organisms cannot use nitrogen gas directly from the atmosphere.
(a) Describe the process of nitrogen fixation and how it enters the food chain.
(b) Explain the role of nitrifying bacteria and denitrifying bacteria in the nitrogen cycle, including the specific conversions they perform.