1. 39.1 The Endocrine System

2. Hormone Substance produced in one part of an organism that affects another part of the same organism.

3. Target Cell Cell that has a receptor for a particular hormone.

4. Exocrine Gland Gland that releases its secretions through tubelike structures called ducts.

5. Endocrine Gland Gland that releases its secretions directly into the bloodstream.

6. Prostaglandin Hormonelike modified fatty acid produced by a wide range of cells; generally affects only nearby cells and tissues.

7. Key Concept The Endocrine system is made up of glands that release their products into the bloodstream. These products deliver messages throughout the body.

8. Key Concept Like most systems of the body, the endocrine system is regulated by feedback mechanisms that function to maintain homeostasis.