Lesson 3: The Endocrine and Exocrine Systems Answers

Use the drop-down menus to identify the terms described below. a group of cells that secretes substances into the blood or directly into an organ a substance produced by cells that helps specific groups of cells to perform specific functions a channel or tube that conveys a substance

are chemical messengers that can travel through the bloodstream and tell cells in the body what to do. They are very important in maintaining homeostasis.

Use the drop-down menus to determine which system the following structures belong to. pituitary gland thyroid gland salivary glands

thyroid gland

salivary glands