2. Essentials of Human Anatomy & Physiology Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slides 9.23 – 9.41 Seventh Edition Elaine N. Marieb Chapter 9 The Endocrine System Lecture Slides in PowerPoint by Jerry L. Cook

3. Thyroid Gland Slide 9.23a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Found at the base of the throat  Consists of two lobes and a connecting isthmus  Produces two hormones  Thyroid hormone  Calcitonin

4. Thyroid Gland Slide 9.23b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.6

5. Thyroid Hormone Slide 9.24 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Major metabolic hormone  Composed of two active iodine- containing hormones  Thyroxine (T 4 ) – secreted by thyroid follicles  Triiodothyronine (T 3 ) – conversion of T 4 at target tissues

7. Calcitonin Slide 9.25 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Decreases blood calcium levels by causing its deposition on bone  Antagonistic to parathyroid hormone  Produced by C (parafollicular) cells Figure 9.9

8. Parathyroid Glands Slide 9.26 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Tiny masses on the posterior of the thyroid  Secrete parathyroid hormone  Stimulate osterclasts to remove calcium from bone  Stimulate the kidneys and intestine to absorb more calcium  Raise calcium levels in the blood

9. Adrenal Glands Slide 9.27 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Two glands  Cortex – outer glandular region in three layers  Medulla – inner neural tissue region  Sits on top of the kidneys

10. Hormones of the Adrenal Cortex Slide 9.28a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Mineralocorticoids (mainly aldosterone)  Produced in outer adrenal cortex  Regulate mineral content in blood, water, and electrolyte balance  Target organ is the kidney  Production stimulated by renin and aldosterone  Production inhibited by atrial natriuretic peptide

11. Hormones of the Adrenal Cortex Slide 9.28b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.10

12. Hormones of the Adrenal Cortex Slide 9.29a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Glucocorticoids (including cortisone and cortisol)  Promote normal cell metabolism  Help resist long-term stressors  Released in response to increased blood levels of ACTH

13. Hormones of the Adrenal Cortex Slide 9.29b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Sex hormones  Produced in the adrenal cortex  Androgens (male) and some estrogen (female)

14. Hormones of the Adrenal Medulla Slide 9.30 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Produces two similar hormones (catecholamines)  Epinephrine  Norepinephrine  These hormones prepare the body to deal with short-term stress

15. Roles of the Hypothalamus and Adrenal Glands in the Stress Response Slide 9.31 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.12

16. Pancreatic Islets Slide 9.32a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  The pancreas is a mixed gland  The islets of the pancreas produce hormones  Insulin – allows glucose to cross plasma membranes into cells from beta cells  Glucagon – allows glucose to enter the blood from alpha cells  These hormones are antagonists that maintain blood sugar homeostasis

17. Pancreatic Islets Slide 9.32b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.13

18. Pancreatic Hormones and Blood Sugar Slide 9.33 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 9.14

19. Pineal Gland Slide 9.34 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Found on the third ventricle of the brain  Secretes melatonin  Helps establish the body’s wake and sleep cycles  May have other as-yet-unsubstantiated functions

20. Thymus Slide 9.35 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Located posterior to the sternum  Largest in infants and children  Produces thymosin  Matures some types of white blood cells  Important in developing the immune system

21. Hormones of the Ovaries Slide 9.36 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Estrogens  Produced by Graafian follicles or the placenta  Stimulates the development of secondary female characteristics  Matures female reproductive organs

22. Hormones of the Ovaries Slide 9.36 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Estrogens  Helps prepare the uterus to receive a fertilized egg  Helps maintain pregnancy  Prepares the breasts  to produce milk

23. Hormones of the Ovaries Slide 9.37 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Progesterone  Produced by the corpus luteum  Acts with estrogen to bring about the menstrual cycle  Helps in the implantation of an embryo in the uterus

24. Hormones of the Testes Slide 9.38 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Interstitial cells of testes are hormone- producing  Produce several androgens

25. Hormones of the Testes Slide 9.38 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Testosterone is the most important androgen  Responsible for adult male secondary sex characteristics  Promotes growth and maturation of male reproductive system  Required for sperm cell production

26. Other Hormone-Producing Tissues and Organs Slide 9.39 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Parts of the small intestine  Parts of the stomach  Kidneys  Heart  Many other areas have scattered endocrine cells

27. Endocrine Function of the Placenta Slide 9.40 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Produces hormones that maintain the pregnancy  Some hormones play a part in the delivery of the baby  Produces HCG in addition to estrogen, progesterone, and other hormones

28. corpus luteum ovary Female reproductive cycle pregnancy maintains uterus lining no yes Feedback estrogen egg matures & is released (ovulation) builds up uterus lining FSH & LH progesterone fertilized egg (zygote) hCG corpus luteum breaks down progesterone drops menstruation corpus luteum maintains uterus lining GnRH pituitary gland hypothalamus

29. Developmental Aspects of the Endocrine System Slide 9.41 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Most endocrine organs operate smoothly until old age  Menopause is brought about by lack of efficiency of the ovaries  Problems associated with reduced estrogen are common  Growth hormone production declines with age  Many endocrine glands decrease output with age