Phosphorus/ˈfɑːsfərəs/ Definition 1 of 2Pro Tip 1/3Biological Significance Phosphorus is vital for life; it's a part of DNA, bones, and teeth. Plants absorb phosphorus from the soil to grow. Pro Tip 2/3Environmental Concern Excess phosphorus in water can cause algae blooms, harming the ecosystem. Runoff from phosphorus-rich fertilizers polluted the lake. Pro Tip 3/3Natural Occurrence Phosphorus is found in rocks and released through weathering processes. The phosphorus cycle starts with the release from rocks.