1. How does the phosphorus cycle differ from both the Nitrogen and Carbon cycles? 2. Compare and contrast the terrestrial and marine phosphorus cycles and how are they related?

3. How is human activity impacting the phosphorus cycle?

4. How do the geochemical phase and ecosystem phases of the phosphorus cycle differ?

Which of the following statements is true about energy quantization at the atomic level? electrons in the outermost orbits are the most stable. electrons in all the orbits around the nucleus have the same amount of energy. electrons in the orbit closest to the nucleus have the least amount of energy. electrons absorb or release the same amount of energy independent of the energy levels.