Active is required to maintain normal blood calcium and phosphorus levels.

Explanation:

This vitamin is also known as the sunlight vitamin because it can be absorbed by the body through sunlight. It work more like a hormone, pushing cells to have receptors for it. One of its most importance is inhibiting intestines to absorb calcium, phosphorus etc; maintaining the use and supply of these elements in our bloodstream.

affects the water bodies: excessive use of fertilizers causes eutrophication. the fertilizers which are used on plants affect the quality of land on which it is used, further causing erosion of soil. the fertilizers used on plants contain harmful chemical fumes which affect the environment.