Question

1 How do animals receive their necessary nitrogen?

2. Why can't plants use nitrogen gas directly?

3. Explain why bacteria are essential parts of the nitrogen cycle.

Answer 1

1. Animals get the nitrogen they need by eating plants or other animals that contain nitrogen.
2. Even though nitrogen gas makes up most of Earth's atmosphere, plants cannot use this nitrogen gas to make organic compounds for themselves and other organisms
3. The nitrogen cycle moves nitrogen back and forth between the atmosphere and organisms. Bacteria change nitrogen gas from the atmosphere to nitrogen compounds that plants can absorb

Answer 2

1.) Animals get the nitrogen they need by eating plants or other animals that contain nitrogen.
2.) nitrogen is “unavailable” to plants, because the gaseous form cannot be used directly by plants without undergoing a transformation. To be used by plants, the N2 must be transformed through a process called nitrogen fixation.
3.) Bacteria help the nitrogen change between states so it can be used. When nitrogen is absorbed by the soil, different bacteria help it to change states so it can be absorbed by plants. Animals then get their nitrogen from the plants.