1. Control of Our Bodies Homeostasis
Endocrine System
Control of Our Bodies Homeostasis

2. Calcium and glucose levels
Explain
Section 39-2
The Endocrine System
regulates
Growth
Water balance
Reproduction
Metabolism
Calcium and glucose levels
Response to stress
by means of the
by means of the
by means of the
by means of the
by means of the
by means of the
Pituitary
Ovaries
Testes
Thyroid
Pancreas
Adrenals
Parathyroids

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

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

5. Endocrine Glands Section 39-1 Hypothalamus Pineal gland
The hypothalamus makes hormones that control the pituitary gland. In addition, it makes hormones that are stored in the pituitary gland.
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.
Pituitary gland
The pituitary gland produces hormones that regulate many of the other endocrine glands.
Pancreas
The pancreas produces insulin and glucagon, which regulate the level of glucose in the blood.
Parathyroid glands
These four glands release parathyroid hormone, which regulate the level of calcium 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.
Thymus
During childhood, the thymus releases thymosin, which stimulates Tcell development.
Testis
The testes produce testosterone, which is responsible for sperm production and the development of male secondary sex characteristics
Adrenal glands
The adrenal glands release epinephrine and nonepinephrine, which help the body deal with stress.

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

7. Hypothalamus Part of brain and attached to pituitary
Controls pituitary secretions

8. Thyroid

9. THYROID GLAND
Regulates
Metabolism and energy balance

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

11. Parathyroid

12. 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

14. 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

15. Adrenal Gland
Releases hormones to deal with stress

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

17. Glucose Regulation
Two Ways:
Eating Regularly
Hormone Adjustments

18. 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.

19. 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

20. 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

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

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