Alkaline Phosphatase: is an enzyme produced primarily in the bone, liver and intestinal tract. It reflects growth or activity in these areas of the body and is often used as a tumor marker. Through its highly alkaline nature, it functions as one of the pH controls in the blood. Increases are seen in some types of tumor, bone injury, pregnancy, gall bladder duct obstruction and skeletal growth. Decreases are seen in low adrenal function and zinc deficiency.