Phosphorus Cycle

Which of the following is an essential function of phosphorus in living organisms?

• Producing heat for body temperature regulation

• Forming the building blocks of DNA and cell membranes

• Acting as a primary source of energy for muscles

• Filtering waste products from the blood

How is phosphorus typically found in the natural world?

• As a pure, uncombined element

• Combined with four oxygen atoms as phosphates

• Only in the atmosphere as a gas

• Primarily as a liquid in underground reservoirs

What happens to phosphate compounds in the soil after plants and animals die or excrete waste?

• They are immediately released into the atmosphere.

• They are taken up by detritivores or returned to the soil.

• They transform into a different element.

• They become permanently trapped in rocks.

What is the main environmental problem caused by excessive phosphorus runoff into aquatic ecosystems?

• Increased water clarity, harming aquatic plants.

• Eutrophication, leading to excessive algae growth and oxygen depletion.

• A decrease in water temperature, affecting marine life.

• Formation of new sedimentary rock layers on the surface.