Advanced Assessment: Carbon, Nitrogen, and Water Cycles

Which of the following BEST explains the role of photosynthesis in the carbon cycle?

• It releases carbon dioxide into the atmosphere.

• It converts atmospheric carbon into organic molecules used by plants.

• It transforms carbon from decomposed organisms into fossil fuels.

• It facilitates the combustion of organic material.

A scientist observes an increase in atmospheric carbon dioxide over the past century. Which of the following is the MOST LIKELY cause?

• Increased photosynthesis due to more plants

• Decreased respiration in organisms

• Increased combustion of fossil fuels

• Greater nitrogen fixation rates

If decomposition rates slowed dramatically, what would be the MOST IMMEDIATE effect on the carbon cycle?

• More carbon would be stored in dead organisms instead of being released.

• Photosynthesis would increase to balance the cycle.

• Carbon dioxide levels in the atmosphere would rise instantly.

• Less carbon would be stored in fossil fuels.

Which of the following processes in the nitrogen cycle makes nitrogen available for plant absorption?

• Nitrogen fixation and nitrification

• De-nitrification and ammonification

• Assimilation and respiration

• Combustion and evaporation

Why is nitrogen fixation a necessary part of the nitrogen cycle?

• It transforms nitrogen into carbon, which plants need.

• It allows plants to absorb nitrogen directly from the atmosphere.

• It converts nitrogen gas into a form that plants can use for growth.

• It decomposes dead organisms into usable nitrogen.

Which process in the nitrogen cycle could be disrupted by excessive use of synthetic fertilizers?

• De-nitrification

• Nitrification

• Transpiration

• Precipitation

A scientist notices an area of soil has become depleted of nitrates. Which of the following would be the BEST solution?

• Burn plant matter to release nitrogen gas

• Add nitrogen-fixing bacteria to the soil

• Increase carbon dioxide levels in the atmosphere

• Introduce more decomposers to reduce ammonia levels

How does ammonification contribute to the nitrogen cycle?

• It converts nitrogen gas into ammonia for plant absorption.

• It breaks down dead organisms and waste, releasing ammonia into the soil.

• It transforms ammonia into nitrates for plant use.

• It removes excess nitrogen from the soil by releasing it as gas.

The water cycle plays a major role in transporting nutrients across ecosystems. Which process in the water cycle is MOST responsible for moving nutrients from the soil into plants?

• Evaporation

• Condensation

• Transpiration

• Precipitation

Which of the following would be the most direct consequence of a prolonged drought on the water cycle?

• Increased condensation rates

• Decreased transpiration from plants

• Increased nitrogen fixation

• More frequent precipitation events