AP BIOLOGY

Detailed explanation-1: -Phosphorus moves in a cycle through rocks, water, soil and sediments and organisms. Over time, rain and weathering cause rocks to release phosphate ions and other minerals. This inorganic phosphate is then distributed in soils and water. Plants take up inorganic phosphate from the soil.

Detailed explanation-2: -Weathering. Since the main source of phosphorus is found in rocks, the first step of the phosphorus cycle involves the extraction of phosphorus from the rocks by weathering. Weather events, such as rain and other sources of erosion, result in phosphorus being washed into the soil.

Detailed explanation-3: -Potassium release was the most important in all rocks; after 2 years of weathering, 19.4% to 46.9% of K was released from the initial parent rocks, which suggested that K release from weathering could meet most of the crop K requirement in purplish soils.

Detailed explanation-4: -Note: In phosphorus cycle, the weathering process makes phosphate available to the soil which are the consumers of phosphate. Phosphate is an important component of cellular and organic molecules. It also plays an important role for the transport of energy.