Question

3 multiple choice 20 points
how is the element phosphorous different from carbon and nitrogen in the biogeochemical cycles?
it cycles through rocks, soil, and water and is not found in the atmosphere.
it cycles only through the water cycle.
it is in the atmosphere only and is cycled by respiration.
it is only found in living organisms.
4 multiple choice 20 points
why is it necessary that the elements carbon, hydrogen, oxygen, nitrogen, and phosphorous be cycled?
they make up only the amino acids needed to produce proteins.
they are used by only by plants to produce carbohydrates.
they make up the macromolecules living organisms need to survive.
they are used only by animals to produce water.

Explanation:

For question 3:

• Phosphorus is mainly in rocks, soil, and water. It doesn't have a significant atmospheric component like carbon (as \(CO_2\)) and nitrogen (as \(N_2\)).

For question 4:

• Carbon, hydrogen, oxygen, nitrogen, and phosphorus are essential for forming macromolecules (e.g., proteins, nucleic acids, carbohydrates, lipids) that living organisms need to survive.

Answer:

1. It cycles through rocks, soil, and water and is not found in the atmosphere.
2. They make up the macromolecules living organisms need to survive.