the phosphorus cycle

Question 1

what is phosphorus?

Answer 1

phosphorus is an important element found in many biological molecules, such as phospholipids, nucleic acids (DNA and RNA), ATP

Question 2

how does the phosphorus cycle differ from the carbon and nitrogen cycle?

Answer 2

unlike the carbon and nitrogen cycle, there are no atmospheric gases involved

Question 3

explain the process of the phosphorus cycle

Answer 3

• saprobionts decompose dead animals/plants/algae/waste materials using extracellular digestion.
• saprobionts absorb the products of digestion and release phosphate ions ((PO4)3-) into soils, lakes, rivers and oceans.
• some of these phosphate ions are absorbed by plants and algae and are used to form biological molecules used in growth, such as phospholipids, ATP and nucleic acids
• the phosphate ions are then passed to the animals that feed on the plants and algae
• dissolved phosphates are washed into oceans where they can, by sedimentation, form rocks
• the phosphates in sedimentary rocks are only returned to the cycle if geological upheavel and erosion occurs