Whole grains are a source of carbohydrates, multiple nutrients and dietary fiber. Sulfur improves the efficiency of other essential plant nutrients, particularly nitrogen and phosphorus. Selenium interacts with other nutrients, such as iodine and vitamin E. Vitamin B is part of the vitamin B group of essential nutrients. Cats have specific requirements for their dietary nutrients. Some phytochemicals are antinutrients that interfere with the absorption of nutrients. These enzymes are involved in the digestion of sebum and the acquisition of other nutrients. It contains many other nutrients including protein and lactose. Microorganisms play an important role in decomposition of organic matter and mineralization of nutrients. Animal prey makes up for differing deficiencies in soil nutrients. It competes with other species for sunlight, moisture and nutrients. They are therefore very sensitive to excessive soil-borne nutrients. Arbuscules are the sites of exchange for phosphorus, carbon, water, and other nutrients. Replenishing the topsoil with lost nutrients provided for bountiful harvests. Symptoms vary from none to severe diarrhea with poor absorption of nutrients.