3How the Endocrine System Works The endocrine system includes various organs that work together to regulate body functions.The endocrine system sends and receives hormones.
4How the Endocrine System Works There are several different endocrine glands.Endocrine glandsDuctless or tubeless organs or groups of cells that secrete hormones directly into the bloodstream
5How the Endocrine System Works Endocrine glands secret hormones into the blood to influence physical and mental responses.HormonesChemical substances that help regulate many of your body’s functions
6How the Endocrine System Works Major Glands of the Endocrine SystemThyroid GlandPineal GlandParathyroid GlandsPituitary GlandTestesThymusOvariesAdrenal GlandsHypothalamusPancreas
7How the Endocrine System Works The thyroid gland produces thyroxine, which regulates the way cells release energy from nutrients.Thyroid glandProduces hormones that regulate metabolism, body heat, and bone growth
8How the Endocrine System Works The parathyroid glands are located in the neck near the thyroid gland.Parathyroid glandsProduce a hormone that regulates the body’s balance of calcium and phosphorus
9How the Endocrine System Works Male reproductive glands that produce sperm for fertilizationTestesOvariesFemale reproductive glands that produce the egg cellsLinks the endocrine system and the nervous system and stimulates the pituitary gland to secrete hormonesHypothalamusPineal GlandSecretes the hormone melatonin, which is thought to affect the onset of puberty, and regulates sleep cyclesThymusRegulates development of the immune systemAdrenal GlandsRegulate the body’s salt and water balance and control the body’s emergency response
10How 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.PancreasA gland that serves both the digestive and the endocrine systems
11The Pituitary: The Master Gland Known as the master gland, the pituitary gland has three sections, or lobes: anterior, intermediate, and posterior.Pituitary glandRegulates and controls the activities of all other endocrine glands
12The Pituitary: The Master Gland Hormones produced by the pituitary gland play a significant role in determining height.
13Anterior Lobe Stimulates normal body growth and development The anterior, or front, lobe of the pituitary gland produces these hormones:Somatotropic, or Growth HormoneStimulates normal body growth and developmentThyroid-Stimulating HormoneStimulates the thyroid gland to produce hormonesAdrenocorticotropic HormoneStimulates production of hormones in the adrenal glandsFollicle-Stimulating Hormone and Luteinizing HormoneStimulates production of all other sex hormones
14Intermediate LobeThe intermediate, or middle, lobe of the pituitary secretes melanocyte-stimulating hormone, which controls the darkening of the pigments in the skin.
15Intermediate LobeThe posterior, or rear, lobe of the pituitary secretes antidiuretic hormone thatregulates the balance of water in the body, andproduces oxytocin, which stimulates the smooth muscles in the uterus during pregnancy, causing contractions during the birth of a baby.
16The Adrenal GlandsThe adrenal glands each have two parts: the adrenal cortex and the adrenal medulla.Adrenal glandsHelp the body deal with stress and respond to emergencies
17The adrenal cortex secretes hormones that The Adrenal GlandsThe adrenal cortex secretes hormones thatinhibit the amount of sodium excreted in urine and maintain blood volume and blood pressureaid in the metabolism of fats, proteins, and carbohydratesinfluence the body’s response to stressplay a role in both the immune response and sexual function
18The Adrenal GlandsThe 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.
19Maintaining 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.
20Maintaining Your Endocrine Health Tips for Maintaining Your Endocrine HealthEat balanced meals to ensure that you get the nutrients you need.Use stress-management techniques.Get 8 ½ to 9 hours of sleep every night.Engage in regular physical activity.Have regular medical checkups.
21Maintaining Your Endocrine Health These Endocrine Disorders May Require MedicationDiabetes mellitusHypothyroidisimHyperthyroidismGoiterOverproduction of adrenal hormones
22After You Read Reviewing Facts and Vocabulary What are hormones?Chemical substances produced in glands that help regulate many body functions
23After You Read Reviewing Facts and Vocabulary Name the hormone that stimulates normal growth and development.Somatotropic hormone
24After You Read Reviewing Facts and Vocabulary What gland helps regulate the chemicals that control sleep?Pineal gland