Endocrine System Control of Our Bodies Homeostasis

Engage You will be viewing some video clips from Sideshow: Alive On The Inside. Within these clips you will see various types of endocrine disorders. If you are interested in viewing more endocrine system oddities, you can read the book Freak Show: Presenting Human Oddities for Amusement and Profit by Robert Bogdan.

Explore Explore 1 Using your text and other resources, you will familiarize yourself with the endocrine glands and their functions by completing the endocrine system worksheet. Explore 2 Role Play: The Rise and Fall of Glucose

regulates Explain Section 39-2 by means of the Growth Water balance ReproductionMetabolism Calcium and glucose levels Response to stress The Endocrine System Pituitary Ovaries TestesThyroidPancreasAdrenals Parathyroids

Explain List 4 types of endocrine glands and give their function. What is the overall function of the endocrine system? With what other systems does the endocrine system interact?

Exocrine or Endocrine Exocrine – release products (enzymes) into ducts –Ex) Sweat, tears, digestive juices Endocrine – directly to bloodstream; NO DUCTS –Ex) Hormones

Endocrine System Glands – release products to bloodstream directly. Horomones – products deliver messages to body Target cells – have specific receptors for specific hormones

Hypothalamus The hypothalamus makes hormones that control the pituitary gland. In addition, it makes hormones that are stored in the pituitary gland. Pituitary gland The pituitary gland produces hormones that regulate many of the other endocrine glands. Parathyroid glands These four glands release parathyroid hormone, which regulate the level of calcium in the blood. Thymus During childhood, the thymus releases thymosin, which stimulates Tcell development. Adrenal glands The adrenal glands release epinephrine and nonepinephrine, which help the body deal with stress. Pineal gland The pineal gland releases melatonin, which is involved in rhythmic activities, such as daily sleep-wake cycles. Thyroid The thyroid produces thyroxine, which regulates metabolism. Pancreas The pancreas produces insulin and glucagon, which regulate the level of glucose in the blood. Ovary The ovaries produce estrogen and progesterone. Estrogen is required for the development of secondary sex characteristics and for the development of eggs. Progesterone prepares the uterus for a fertilized egg. Testis The testes produce testosterone, which is responsible for sperm production and the development of male secondary sex characteristics Section 39-1 Endocrine Glands

Pituitary Gland Master gland –Controls the other endocrine glands Growth Hormone (GH) –Too much – gigantism –Too little – dwarfism Antidiuretic (ADH) –Stimulates kidneys to keep water

Hypothalamus Part of brain and attached to pituitary Controls pituitary secretions

Thyroid

THYROID GLAND Regulates –Metabolism and energy balance

Thyroid Hormones Thyroxine –Regulates body energy usage Calcitonin –One hormones that regulates calcium and phosphate in blood

Questions What are the two hormones that the thyroid secretes? What is the function of thyroxine? What is the function of calcitonin?

Parathyroid

Calcium Regulation PARAthyroid Glands PTH-Parathyroid hormones Increases calcium, phosphate, and magnesium absorption in intestines. Causes bones to release calcium and phosphate Causes removal of calcium and magnesium from urine by kidneys Increases the making of Vitamin D in body

Negative Feedback Mechanism Our body uses feedback mechanism to maintain homeostasis within our body. Regulation of calcium is one example of this process. Can you think of another one? Hint: Role Play Activity

Questions PTH cause the small intestine to absorb more calcium, _____ and _____. What does PTH cause the bones to release? What do the kidneys do because of PTH?

Adrenal Gland Releases hormones to deal with stress

Adrenal Gland Cont. Cortex –Produces more than 2 dozen steroid hormones –corticosteriods Medulla –“fight or flight” –Epinephrine and norepinephrine

Glucose Regulation Two Ways: 1.Eating Regularly 2.Hormone Adjustments

Pancreas: Endocrine and Exocrine What did the pancreas do in digestion? Secreted Enzymes Pancreas also secretes hormones Endocrine glands - ductless organ that releases hormones DIRECTLY into the bloodstream.

Questions What do exocrine glands secrete? What do endocrine glands secrete?

Blood Glucose Level Pancreatic Hormones regulate blood sugar level before and after meals. Islets; clusters of cells in pancreas –Alpha  secrete glucagon – increases sugar –Beta  secrete insulin – decreases sugar

What Happens? Between meals Blood glucose low  Pancreas secretes glucagon  Liver changes glycogen to glucose  glucose sent to target tissues After a meal Blood glucose high  Pancreas secretes insulin  Glucose goes to the Liver(Glygogen) and goes to Target tissues

Questions What organ regulates glucose in blood? When we eat our blood glucose level is high or low? In between meals our blood glucose level is high or low? When our blood glucose is high the pancreas secretes ___________. When our blood glucose is low the pancreas secretes ___________. What mechanism allows our body to control the glucose level in our body?

Diabetes –High sugar levels in blood –Do not produce enough insulin to control blood sugar –Some take insulin injections to regulate

Reproductive Glands Production of gametes Secretion of sex hormones Female – Ovaries - Estrogen Males – Testes - Testosterone

Elaborate You will perform various investigations with plant hormones to better understand human hormones. You will be working with hormones that stimulate and inhibit plant growth.