1. Life Science 4.3 The Endocrine System

2. Objectives: Explainwhy the endocrine system is important to the body. Identify five glands of the endocrine system, and describe what their hormones do. Describe how feedback mechanisms stop and start hormone release. Name two hormone imbalances.

3. Hormones as Chemical Messengers Endocrine system Collection of glands and groups of cells that secrete hormones. Gland group of cells that make special chemical messengers, called hormones, for your body. Hormone Chemical messenger made in one cell or tissue that causes a change in another cell or tissue in another part of the body.

4. Adrenal Glands Epinephrine – also known as adrenaline, is released in “fight or flight” response. Prepares you to fight or run from danger.

5. More Endocrine Glands Thyroid gland Controls the secretion of growth hormones for normal body growth. Thymus gland Produces killer T cells that help destroy or neutralize cells or substances that invade your body. Metabolism Sum of all the chemical processes that take place in an organism.

7. Controlling the Endocrine Glands Endocrine glands control feedback mechanisms in the body. Occasionally, an endocrine gland makes too much or not enough of a hormone. For example, sometimes a child’s pituitary gland doesn’t make enough growth hormone. As a result, the child’s growth is stunted. Hormone Imbalances