The Endocrine System (2:30) Click here to launch video Click here to download print activity

Your endocrine system sends and receives chemical messages that control many body functions.

endocrine glands hormones thyroid gland parathyroid glands pancreas pituitary glands adrenal glands

How the Endocrine System Works The endocrine system includes various organs that work together to regulate body functions. The endocrine system sends and receives hormones.

How the Endocrine System Works There are several different endocrine glands. Endocrine glands Ductless or tubeless organs or groups of cells that secrete hormones directly into the bloodstream

How the Endocrine System Works Endocrine glands secret hormones into the blood to influence physical and mental responses. Hormones Chemical substances that help regulate many of your body’s functions

How the Endocrine System Works Major Glands of the Endocrine System Thyroid Gland Parathyroid Glands Testes Ovaries Hypothalamus Pineal Gland Pituitary Gland Thymus Adrenal Glands Pancreas

How the Endocrine System Works The thyroid gland produces thyroxine, which regulates the way cells release energy from nutrients. Thyroid gland Produces hormones that regulate metabolism, body heat, and bone growth

How the Endocrine System Works The parathyroid glands are located in the neck near the thyroid gland. Parathyroid glands Produce a hormone that regulates the body’s balance of calcium and phosphorus

How the Endocrine System Works Testes Ovaries Hypothalamus Pineal Gland Thymus Adrenal Glands Male reproductive glands that produce sperm for fertilization Female reproductive glands that produce the egg cells Links the endocrine system and the nervous system and stimulates the pituitary gland to secrete hormones Secretes the hormone melatonin, which is thought to affect the onset of puberty, and regulates sleep cycles Regulates development of the immune system Regulate the body’s salt and water balance and control the body’s emergency response

How the Endocrine System Works The pancreas is an endocrine gland that secretes two hormones—glucagon and insulin—that regulate the level of glucose in the blood. Pancreas A gland that serves both the digestive and the endocrine systems

The Pituitary: The Master Gland Known as the master gland, the pituitary gland has three sections, or lobes: anterior, intermediate, and posterior. Pituitary gland Regulates and controls the activities of all other endocrine glands

The Pituitary: The Master Gland Hormones produced by the pituitary gland play a significant role in determining height.

Sultan Kösen 8 feet 3 in.

Robert Wadlow 8 feet 11.1 inches

Dwarfism

Anterior Lobe Somatotropic, or Growth Hormone Stimulates normal body growth and development Thyroid-Stimulating Hormone Adrenocorticotropic Hormone Follicle-Stimulating Hormone and Luteinizing Hormone Stimulates the thyroid gland to produce hormones Stimulates production of hormones in the adrenal glands Stimulates production of all other sex hormones The anterior, or front, lobe of the pituitary gland produces these hormones:

Intermediate Lobe The intermediate, or middle, lobe of the pituitary secretes melanocyte-stimulating hormone, which controls the darkening of the pigments in the skin.

Intermediate Lobe The posterior, or rear, lobe of the pituitary secretes antidiuretic hormone that regulates the balance of water in the body, and produces oxytocin, which stimulates the smooth muscles in the uterus during pregnancy, causing contractions during the birth of a baby.

The Adrenal Glands The adrenal glands each have two parts: the adrenal cortex and the adrenal medulla. Adrenal glands Help the body deal with stress and respond to emergencies

The Adrenal Glands The adrenal cortex secretes hormones that inhibit the amount of sodium excreted in urine and maintain blood volume and blood pressure aid in the metabolism of fats, proteins, and carbohydrates influence the body’s response to stress play a role in both the immune response and sexual function

The Adrenal Glands The adrenal medulla secretes the hormones epinephrine (also called adrenaline) and norepinephrine. Epinephrine increases heartbeat and respiration, raises blood pressure, and suppresses the digestive process during periods of high emotion.

Maintaining Your Endocrine Health To keep your endocrine system working at its peak, you need to follow sound health practices. Your endocrine health is directly related to your overall health.

Maintaining Your Endocrine Health Get 8 ½ to 9 hours of sleep every night. Use stress-management techniques. Eat balanced meals to ensure that you get the nutrients you need. Tips for Maintaining Your Endocrine Health Engage in regular physical activity. Have regular medical checkups.

Maintaining Your Endocrine Health Hyperthyroidism Hypothyroidisim Diabetes mellitus These Endocrine Disorders May Require Medication Goiter Overproduction of adrenal hormones

After You Read Reviewing Facts and Vocabulary Chemical substances produced in glands that help regulate many body functions 1.What are hormones?

After You Read Reviewing Facts and Vocabulary 2.Name the hormone that stimulates normal growth and development. Somatotropic hormone

After You Read Reviewing Facts and Vocabulary 3.What gland helps regulate the chemicals that control sleep? Pineal gland