Question

1. fill in the blanks from the example they go over related to how carbon moves from reservoir to reservoir: carbon dioxide in atmosphere - photosynthesis - __________ - cellular respiration - __________ - converts to fossil fuels - burning sends carbon dioxide back into atmosphere
2. how can nitrogen be fixed?
3. how can nitrogen be problematic?

Explanation:

1. During photosynthesis, carbon - dioxide is converted into organic compounds in plants. After cellular respiration in organisms, the remains of organisms are decomposed and can eventually form fossil fuels.
2. Nitrogen can be fixed by nitrogen - fixing bacteria in the soil, lightning which causes nitrogen and oxygen in the air to react, and industrial processes like the Haber - Bosch process to produce ammonia.
3. Nitrogen can be problematic when there is an excess of it in ecosystems. For example, excessive nitrogen runoff into water bodies can cause eutrophication, leading to algal blooms that deplete oxygen and harm aquatic life. Also, increased nitrogen in the atmosphere can contribute to air pollution and climate change through the formation of nitrous oxide, a potent greenhouse gas.

Answer:

1. Organic Compounds in Plants; Decomposition of Organisms
2. By nitrogen - fixing bacteria, lightning, and industrial processes.
3. Causes eutrophication in water bodies and contributes to air pollution and climate change.