These organic compounds can also have amounts of nitrogen, calcium and phosphorous. They may have varying small amounts of other elements called “trace elements” like potassium, iodine, sulfur, iron, magnesium and sodium.
Living things also need inorganic compounds like water and salts.
Water is an essential part of every living thing. Plants use water in deriving some of their nutrients from minerals in the soil. These minerals have to be dissolved in water in order to be absorbed by the plants.
Water being liquid can easily hold and transport other materials. Water provides a way for substances to reach all the cells in an organism.
Animals and especially man depend much on water. Water is taken into the body by eating plants and meats and by drinking beverages. Humans can go for a month without eating but will die in 3 to 5 days without water because our bodies are made up of about 70 percent water. The body uses water in maintaining its temperature, breathing, digesting food, and lubricating moving joints.