How Nutrients Get in, and Wastes Get Out

Endocrine System
The endocrine system deals with hormones, which regulate the metabolic rates of cells and organs. They are much like nerves, but target only certain parts of the body. They are essential to maintain homeostasis. The gastrin hormone is found in the stomach, and controls the amount of gastric juice produced. They also regulate excretions such as saliva. The hormones controlling the digestive and excretory systems are located some distance away from the cells that they have to control, therefore some method of transport must be utilized. This method is the bloodstream. The hormonal glands secrete their hormones into the bloodstream. These hormones then travel to the target organ or cell, and regulate the activity of that organ or cell. This system is slower to respond than the nervous system.
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