1. © 2010 Delmar, Cengage Learning 1 PowerPoint Presentation to Accompany

2. © 2010 Delmar, Cengage Learning 2 Chapter 12 The Endocrine System

3. © 2010 Delmar, Cengage Learning 3 Introduction Maintains internal environment (homeostasis) Hypothalamus: sends chemical signals to pituitary Endocrine glands –Ductless –Secrete hormones directly into bloodstream

4. © 2010 Delmar, Cengage Learning 4 Introduction (cont’d.)

5. © 2010 Delmar, Cengage Learning 5 5 The Functions of Hormones

6. © 2010 Delmar, Cengage Learning 6 The Functions of Hormones Control cellular respiration, growth and reproduction Control body fluids and electrolyte balance Control secretion of other hormones Control behavior patterns Regulate reproductive cycles, growth and development

7. © 2010 Delmar, Cengage Learning 7 The Functions of Hormones (cont’d.) Chemical control functions as negative feedback loop –Thermostat turns furnace on when temperature falls below set point Hormones function similarly

8. © 2010 Delmar, Cengage Learning 8 8 The Classification of Hormones

9. © 2010 Delmar, Cengage Learning 9 The Classification of Hormones Modified amino acids –Epinephrine, oxytocin Proteins –Insulin, growth hormones Steroid –Cortisol, estrogen

10. © 2010 Delmar, Cengage Learning 10 © 2010 Delmar, Cengage Learning 10 The Hypothalamus of the Brain

11. © 2010 Delmar, Cengage Learning 11 The Hypothalamus of the Brain Controls secretions of the pituitary gland Nerve cells produce chemical signals –Releasing hormones –Releasing inhibitory hormones –Controlled by negative feedback from endocrine system

12. © 2010 Delmar, Cengage Learning 12 © 2010 Delmar, Cengage Learning 12 The Major Endocrine Glands and Their Hormones

13. © 2010 Delmar, Cengage Learning 13 The Anterior Pituitary Gland, Its Hormones and Some Disorders Growth hormone (GH): cell metabolism and growth –Decreased production Dwarfism: childhood –Increased production Gigantism: childhood Acromegaly: post puberty –Controlled by two releasing hormones from hypothalamus

14. © 2010 Delmar, Cengage Learning 14 The Anterior Pituitary Gland (cont’d.) Thyroid-stimulating hormone (TSH): stimulates thyroid Adrenocorticotropic hormone (ACTH): stimulates adrenal cortex Melanocyte-stimulating hormone (MSH): stimulates melanocytes

15. © 2010 Delmar, Cengage Learning 15 The Anterior Pituitary Gland (cont’d.) Follicle-stimulating hormone (FSH) –Females Stimulates ovarian follicle development –Males Stimulates sperm cell production

16. © 2010 Delmar, Cengage Learning 16 The Anterior Pituitary Gland (cont’d.) Luteinizing hormone (LH) –Females Stimulates ovulation and progesterone production –Males Testosterone production Lactogenic hormone (prolactin): stimulates milk production in females –May cause decrease in male sex hormones

17. © 2010 Delmar, Cengage Learning 17 The Posterior Pituitary Gland and Its Hormones Antidiuretic hormone (ADH) –Increased water reabsorption in kidney tubules –Deficiency results in diabetes insipidus –Regulated through osmoreceptors Dehydration causes water conservation

18. © 2010 Delmar, Cengage Learning 18 The Posterior Pituitary Gland and Its Hormones (cont’d.) Oxytocin –Contraction of uterine smooth muscles –Constriction of mammary gland cells (lactation) –Given after childbirth to constrict blood vessels to minimize risk of hemorrhage

19. © 2010 Delmar, Cengage Learning 19 The Thyroid Gland, Its Hormones and Some Disorders Located below larynx on either side of trachea Requires iodine

20. © 2010 Delmar, Cengage Learning 20 The Thyroid Gland, Its Hormones and Some Disorders (cont’d.) Hormones –Thyroxine (T 4 ): metabolism –Triiodothyronine (T 3 ): metabolism –Calcitonin: regulation of calcium and phosphate concentration

21. © 2010 Delmar, Cengage Learning 21 The Thyroid Gland, Its Hormones and Some Disorders (cont’d.) Hypothyroidism –Cretinism –Lowered metabolic rate –Myxedema Hyperthyroidism –Elevated metabolism –Graves’ disease Exophthalmia

22. © 2010 Delmar, Cengage Learning 22 The Parathyroid Glands, Their Hormones and Some Disorders Located within the posterior thyroid gland Chief cells secrete parathormone (PTH) PTH stimulates bone cell release of calcium and phosphate Hyperparathyroidism –Breakdown of bone matrix Hypoparathyroidism –Low calcium level in blood

23. © 2010 Delmar, Cengage Learning 23 The Parathyroid Glands (cont’d.) Position of the parathyroid glands

24. © 2010 Delmar, Cengage Learning 24 The Adrenal Glands, Their Hormones and Some Disorders Located on top of each kidney Adrenal medulla: epinephrine and norepinephrine Adrenal cortex: aldosterone, cortisol, androgens

25. © 2010 Delmar, Cengage Learning 25 The Adrenal Glands (cont’d.) Disorders –Addison’s disease: lack of adrenal cortex hormones –Cushing’s Syndrome: too much adrenal cortex hormones

26. © 2010 Delmar, Cengage Learning 26 The Pancreas, Its Hormones and Some Disorders Islets of Langerhans Beta cells: insulin production Alpha cells: glucagon production Blood glucose levels regulated by negative feedback

27. © 2010 Delmar, Cengage Learning 27 The Pancreas, Its Hormones and Some Disorders(cont’d.) Disorders –Low blood glucose: acidosis –High blood glucose: excess kidney production, dehydration –Diabetes mellitus: insufficient insulin production

28. © 2010 Delmar, Cengage Learning 28 The Testes and the Ovaries Testes: testosterone –Development of male reproduction structures –Development of male sex characteristics Ovaries: estrogen and progesterone –Development of female reproductive organs –Development of female sex characteristics –Control menstrual cycle

29. © 2010 Delmar, Cengage Learning 29 The Thymus Gland and Its Hormone Located behind the sternum Secretes thymosin Important for T-cell production Thymus shrinks as we age

30. © 2010 Delmar, Cengage Learning 30 The Pineal Gland and Its Hormone Located in the brain near the thalamus Melatonin –Inhibits reproductive functions –Regulates body rhythms Serotonin: neurotransmitter and vasoconstrictor –Stimulates smooth muscle contractions

31. © 2010 Delmar, Cengage Learning 31 Animation – Endocrine System [Insert Endocrine System.swf]

32. © 2010 Delmar, Cengage Learning 32 Summary Discussed the functions of hormones Classified hormones into their major chemical categories Described how the hypothalamus controls the endocrine system Named the major endocrine glands and described the effects of their hormones on the body