Understanding the Endocrine System: Key Functions and Important Glands

1. The Endocrine System By Jonathan Gonzalez, Aaron Mednick, Matt Solórzano, Grant Zitomer

2. What Does It Mean? • Endo: within • Crinis: secrete Opposed to exocrine system, which excretes substances into external environment such as sweat and saliva

4. Physiology • Releasing hormones into bloodstream • Many organs and glands work in tandem • Functions: • Controlling internal chemical environment • Responding to change in case of emergency (i.e. infection) • Regulating metabolism and energy balance • Contributing to growth and development

5. Important Glands and Organs • Hypothalamus: part of brain, secretes hormones; controls homeostasis • Pineal Body/Gland: produces melatonin (helps regulate circadian rhythm [i.e. sleep]) • Pituitary Gland: regulates all endocrine gland functions • Thyroid Gland: important for regulating metabolism • Ovaries: produce egg cells, estrogen, and progesterone

6. Important Glands and Organs, cont'd • Parathyroid Glands: regulate body calcium balance • Thymus: trains T-Lymphocytes (WBC) • Adrenal Glands: produce and release adrenaline & cortisol responding to stress • Kidneys: process blood to filter out waste products • Pancreas: assists in digestion and hormone production • Testes: produce testosterone and sperm

7. Hypothalamus • Located within the brain near optic chiasm • Secretes hormones which control anterior pituitary • Controls: • Water Balance • Sleep • Temperature • Appetite • Blood Pressure

8. Hypothalamus, cont'd • Releases into the pituitary gland • Dopamine • Thyrotropin-releasing hormone • Corticotropin-releasing hormone • Gonadotropin-releasing hormone • Growth hormone-releasing hormone • Somatostatin

9. PituitaryGland • Not part of the brain, but protrudes off of hypothalamus • Controls: • Growth • Sex organs • Metabolism • Water balance • Temperature

10. Pituitary Gland, cont'd • Prolactin • Stimulates mammary glands • Causes sexual arousal • Thyrotropin • Stimulates thyroid • Growth hormone • Stimulates development and growth

11. Pineal Body/Gland • Located in the brain • Produces melatonin that affects: • Sleep/wake patterns • Seasonal functions

12. Thyroid Gland • Located below the Adam's Apple in the neck • Controls metabolism • How fast the body reacts to hormones • Protein production rate • Energy usage speed

13. Thyroid Gland, cont'd • Thyroid stimulating hormone (TSH) activates: • Triiodothyronine (T3) which controls • Body temperature • Heart rate • Growth • Thyroxine (T4) which controls • Rate of protein synthesis • Growth • Produces ATP from glucose • These two hormones affect almost all physiological processes in the body

14. Parathyroid Glands • Located behind to the thyroid gland • Regulates all calcium in the body • Calcium is the only mineral that has its own regulatory system. • Provides electrical energy to muscles and nervous system (via calcium regulation) • Provides strength to skeletal system (via calcium regulation)

15. Parathyroid Glands, cont'd • Produces Parathormone • Increases concentration of calcium in blood • Stimulates osteoclasts • Increases calcium reabsorption in kidneys (to the bloodstream) • Produces Calcitonin • decreases concentration of calcium in blood • Inhibits osteoclast activity in bones • Increases amount of calcium in urine

16. Thymus • Trains T-Lymphocytes (also known as T-Cells) • Part of immune system as well • Part of endocrine for use of hormones in training

17. Adrenal (Suprarenal) Glands • Located superior to both kidneys • Responsible for releasing hormones in response to stress • Cortisol: stress and low glucose • Epinephrine: "fight or flight" • Produce androgen • Controls and maintains development of male characteristics in vertebrates (primary androgen is testosterone)

18. Adrenal Glands, cont'd • Produce aldosterone • Increase reabsorption of water in kidney • Results in increased blood pressure

19. Kidneys • A natural "filter" for the endocrine system • Processes the blood to sift out waste products and extra water • Waste and extra water is excreted as urine

20. Pancreas • A dual function organ • Produces several important hormones • Insulin: lowers blood glucose levels • Glucagon: raises blood glucose levels • Also secretes digestive enzymes which assist the stomach

21. Ovaries • Located in groin area of females • Produces: • Egg Cells (for reproduction) • Estrogen • Progesterone: the "pregnancy hormone"

22. Estrogen • Develops secondary female characteristics • Enlargement of breasts • Widening of hips • Growth of pubic hair • Regulates menstruation

23. Progesterone • Effects: • Prepares uterus for implantation • Makes vaginal skin impenetrable to sperm • Decreased levels lead to: • Menstruation if not pregnant • Labor if pregnant

24. Testes/Testicles • Located in groin area of males • Produces: • Testosterone: develops male reproductive tissues; increases muscle mass • Sperm: fuse with egg cells during fertilization

25. Testosterone • Develops secondary male characteristics • Body hair • Facial hair • Muscle growth • Deepens voice • Adam's Apple • Sperm creation

26. Disorders • Occur due to the increase or decrease of endocrine hormones, which may be caused by: • Problems with endocrine feedback • Failure of a gland to stimulate another gland to release its hormone • Genetics • Infection • Injury to an endocrine gland • Tumor in an endocrine gland

27. Adrenal Insufficiency • The adrenal glands do not release enough cortisol and sometimes aldosterone • Symptoms: • Muscle weakness, loss of appetite, weight loss • Nausea, vomiting, diarrhea, headache, sweating • Low blood pressure, low blood glucose

28. Hyper/Hypothyroidism • Hyperthyroidism • High heart rate • Tremors • Weight loss • Hypothyroidism • Low heart rate • Fatigue • Weight gain • Growth stunting

29. Gigantism and Acromegaly • Caused by the secretion of excess growth hormone from the pituitary gland • Gigantism: during childhood • Acromegaly: during adulthood • Usually tumors in the gland cause these disorders

30. Multiple Endocrine Neoplasia (MEN) • Rare genetic disorder • Causes tumors which cause overproduction in affected glands: • Parathyroid • Adrenal • Thyroid

31. Testing for Disorders • Visit an Endocrinologist: • Conduct urine and blood tests • Imagine test pinpoint tumors • Check hormone levels • Treatment • Difficult because complication with one hormone balance affects other hormone balances • Routine blood work to track imbalance

32. Relationship Between Endocrine System and Other Systems • Reproductive System - hormones control development of reproductive organ; regulates production of gametes • Respiration System - hormones regulate breathing rate • Skeletal System - hormones regulate bone growth/ calcium concentration • Muscular System - hormones regulate muscle metabolism • Excretory System - hormones control water conservation in kidneys • Immune System - parathyroid regulates calcium levels; cortisol can be used as an immunosuppressant

33. To Recap... • Regulates homeostasis • Is in control of the body's hormones • These hormones tell many things in the body what to do, from growing to breathing to giving birth So remember to thank your endocrine system

34. Works Cited http://www.medterms.com/script/main/art.asp?articlekey=3791 http://www.britannica.com/EBchecked/topic/118220/circadian-rhythm http://www.britannica.com/EBchecked/topic/460967/pineal-gland http://www.medterms.com/script/main/art.asp?articlekey=3791 http://www.yourhormones.info/hormones/calcitonin.aspx http://www.britannica.com/EBchecked/topic/186893/human-endocrine-system http://www.nlm.nih.gov/medlineplus/ency/article/001174.htm http://women.webmd.com/guide/understanding-thyroid-problems-basics http://www.webmd.com/digestive-disorders/picture-of-the-pancreas http://www.britannica.com/EBchecked/topic/435788/ovary http://www.nlm.nih.gov/medlineplus/ency/article/002380.htm http://www.hormone.org/Pituitary/overview.cfm