1. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Chapter 10 Lecture Slides

2. Learning Outcomes The Nature of Hormones 1. Distinguish between endocrine and exocrine glands. 2. Distinguish between hormones and prostaglandins. 3. Explain the negative-feedback control of hormone secretion. Pituitary Gland 4. Describe the control and actions of anterior lobe hormones. 5. Describe the control and actions of posterior lobe hormones. 6. Describe the major disorders.

3. Learning Outcomes Thyroid Gland 7. Describe the control and actions of thyroid hormones. 8. Describe the major disorders. Parathyroid Glands 9. Describe the control and actions of parathyroid hormone. 10. Describe the major disorders. Adrenal Glands 11. Describe the control and actions of adrenal hormones.

4. Learning Outcomes Pancreas 12. Describe the control and actions of pancreatic hormones. 13. Describe the major disorders. Gonads 14. Describe the control and actions of male and female gonadal hormones. Other Endocrine Glands and Tissues 15. Describe the action of melatonin. 16. Describe the function of the thymus.

5. Endocrine system provides slow, long lasting coordination of body functions It consists of glands and tissues that secrete hormones Hormones are transported by blood to other tissues and organs

7. –Hormone secretion is regulated by negative feedback A hormone secreted when the concentration of a substance is too low The hormone causes body cells to bring the substance level back to normal Once normal levels are reached, hormone secretion and concentration decreases

8. 10.2 Pituitary Gland (hypophysis) Attached to the hypothalamus by a short stalk Consists of two parts with different functions –Anterior lobe –Posterior lobe

9. Anterior Lobe Hormones Growth hormone (GH) –Stimulates the division and growth of body cells Promotes synthesis of proteins and other biological molecules Increases available energy for producing these molecules –Most abundant during growth years

10. –Disorders Giantism is caused by excess GH during growing years –Extremely tall Acromegaly is caused by excess GH after growth years –Only bones of hands, face, and feet continue to grow Hypopituitary dwarfism is caused by too little GH during growth years –Well proportioned body parts but small in stature

11. Thyroid-Stimulating Hormone (TSH) –Stimulates the thyroid gland to produce thyroid hormone –Regulates metabolism

12. Adrenocorticotropic Hormone (ACTH) –Controls secretion of hormones by the a portion of the adrenal cortex –Releases cortisol –Excess stress can cause excess ACTH production

13. Gonadotropins –There are two types of gonadotropins Follicle-stimulating hormone (FSH) Luteinizing hormone (LH)

14. –FSH functions Females: promotes development of ovarian follicles Males: promotes sperm production –LH functions Females: stimulates ovulation and progesterone production Males: stimulates testosterone production

15. Prolactin –Initiates and maintains milk production by mammary glands after child birth

16. Posterior Lobe Hormones Hormones are produced by neurons in the hypothalamus Two types of hormones are released from the posterior lobe –Antidiuretic hormone (ADH) –Oxytocin

17. Antidiuretic Hormone (ADH) –Promotes water reabsorption by the kidneys to reduce water volume in urine Helps regulate blood volume and blood pressure

18. Oxytocin –Stimulates and strengthens contraction of smooth muscle of the uterus during labor –Causes milk ejection due to infant suckling –Secretion is controlled by positive feedback

19. Calcitonin –Another hormone produced by the thyroid gland –Lowers blood calcium by stimulating calcium deposition by osteoblasts in bones

20. 10.4 Parathyroid Glands Small glands on posterior surface of the thyroid gland Two glands on each lobe

21. Parathyroid Hormone (PTH) –Increases the concentration of blood calcium levels three ways Promotes calcium removal from bones by osteoclasts and inhibiting calcium deposition by osteoblasts Promotes calcium absorption into blood by the intestine

22. 10.5 Adrenal Glands or Suprarenal Glands 2 adrenal glands, one atop each kidney Glands consist of two portions –Inner adrenal medulla –Outer adrenal cortex

23. Hormones of Adrenal Medulla –Secretes epinephrine and norepinephrine –Regulated by sympathetic division of the autonomic nervous system Secreted during times of stress

24. Disorders –Cushing’s syndrome is due to excess ACTH Symptoms –High blood pressure –High blood glucose level –Protein loss –Osteoporosis –Fat accumulation on trunk –Fatigue –Edema –Decreased immunity –Full, round face

25. 10.6 Pancreas Elongated organ posterior to the stomach Secretes digestive enzymes Releases insulin to decrease blood sugar. Glucagon to increase blood sugar

26. –Blood glucose controls secretion by negative feedback Low blood glucose stimulates secretion High blood glucose inhibits secretion

27. 10.7 Gonads Gonads are sex glands –Females: ovaries Produce ova and sex hormones –Males: testes Produce sperm and sex hormones

28. Female Hormones –Ovaries Located in pelvic cavity Small, almond shaped Activate at puberty in response to FSH and LH FSH and LH interact in a 28-day ovarian cycle

29. –Estrogens, primary female sex hormone Secreted by developing ovarian follicles Functions –Development and maturation of female sex organs –Secondary sex characteristics –Maintain uterine lining during pregnancy

30. –Progesterone Functions –Prepare uterus for receiving an embryo –Maintains pregnancy –Prepares mammary glands for milk production

31. Male Hormone –Testes Paired, ovoid organs located in scrotum Interstitial cells secrete testosterone –Testosterone, male sex hormone Functions –Development and maturation of male sex organs –Secondary sex characteristics –Male sex drive

32. 10.8 Other Endocrine Glands and Tissues Other glands and tissues in the body can also secrete hormones –Pineal gland –Thymus gland –Small glands of stomach and small intestine –Placenta

33. Pineal Gland –Small, cone-shaped gland within the brain –Secretes melatonin –Melatonin functions Regulates wake-sleep cycles: makes the body sleepy –When exposed to light, melatonin production is reduced –At night, melatonin production is increased

34. Thymus –Large in infants but gets smaller with age –Functions Crucial role in development of immunity Produces thymosin, which aids in lymphocyte maturation