© 2009 The McGraw-Hill Companies, Inc. All rights reserved The Endocrine System PowerPoint® presentation to accompany: Medical Assisting Third Edition Booth, Whicker, Wyman, Pugh, Thompson

© 2009 The McGraw-Hill Companies, Inc. All rights reserved 34-2 Learning Outcomes 34.1Define the term endocrine glands. 34.2Describe the general functions of the endocrine system. 34.3Define the term hormone. 34.4Explain the difference in hormone control by positive and negative feedback loops.

© 2009 The McGraw-Hill Companies, Inc. All rights reserved 34-3 Learning Outcomes (cont.) 34.5Describe the locations of the hypothalamus, pituitary gland, pineal body, thyroid gland, parathyroid glands, adrenal glands, pancreas, thymus, and gonads. 34.6List the hormones released by the pituitary gland and give the functions of each. 34.7List the hormones released by the thyroid gland and parathyroid glands and give the functions of each.

© 2009 The McGraw-Hill Companies, Inc. All rights reserved 34-4 Learning Outcomes (cont.) 34.8List the hormones released by the adrenal glands and give the functions of each. 34.9List the names of the endocrine cells of the pancreas, the hormones released by them, and the function of each hormone List the hormones released by the pineal body, thymus, and gonads, and give the functions of each.

© 2009 The McGraw-Hill Companies, Inc. All rights reserved 34-5 Learning Outcomes (cont.) 34.11Name the hormones produced by the kidneys and heart, listing which organ produces the hormone, and the hormone’s function Describe stressors and their effect on the body Describe the causes, signs and symptoms, and treatment of various endocrine disorders.

© 2009 The McGraw-Hill Companies, Inc. All rights reserved 34-6 target tissues Introduction  The endocrine system includes the organs of the body that secrete hormones directly into body fluids such as blood Regulates chemical reaction in cells and therefore control functions of the organs, tissues, and other cells Glands secrete hormones into bloodstream to

© 2009 The McGraw-Hill Companies, Inc. All rights reserved 34-7 Hormones  Endocrine glands Ductless Release hormones  Directly into target tissues  Into bloodstream to be carried to target tissues  Hormones – chemicals secreted by a cell that affect the functions of other cells

© 2009 The McGraw-Hill Companies, Inc. All rights reserved 34-8 Hormones (cont.)  Many are derived from steroids that easily cross the cell membrane  Examples of steroid hormones Estrogen Progesterone Testosterone Cortisol hormones

© 2009 The McGraw-Hill Companies, Inc. All rights reserved 34-9 Hormones (cont.)  Nonsteroidal hormones Made of amino acids or proteins and cannot cross the cell membrane easily Bind to receptors on the surface of the cells G-protein – activated by the hormone-receptor complex  Activates enzymes inside cell  Prostaglandins Local, or tissue, hormones Derived from lipid molecules Do not travel in the bloodstream Target tissues are located close by Produced by organs such as  Kidneys  Heart  Stomach  Uterus  Brain

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Negative and Positive Feedback Loops  Control hormone levels  Negative feedback loop Hormone release stops in response to decrease in stimulus  Stimulus (eating) raises blood glucose levels  Pancreas releases insulin in response to elevated blood glucose  Blood glucose decreases as it is used by the body or stored in the liver  Insulin release stops as blood glucose levels normalize

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Negative and Positive Feedback Loops (cont.)  Positive feedback loop As long as stimulus is present, action of hormone continues  Infant nursing at mother’s breast  stimulates hypothalamus  stimulates posterior pituitary  Oxytocin released  stimulates milk production and ejection from mammary glands  Milk release continues as long as infant continues to nurse

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Apply Your Knowledge Match the following: ___Chemicals that effect cell functionA.Nonsteroidal hormone ___Easily cross cell membranesB.Steroidal hormone ___Made of amino acidsC.G-protein ___Target nearby cellsD.Prostaglandins ___Activated by hormone-receptor E.Hormones complex ___Cannot cross cell membranes easily ___Estrogen and cortisol B A D C A B E ANSWER:

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Hypothalamus  Hormones Oxytocin Antidiuretic hormone (ADH)  Hormones transported to the posterior pituitary for storage  Directs posterior pituitary to release hormones Glands

© 2009 The McGraw-Hill Companies, Inc. All rights reserved  Controlled by the hypothalamus  Located at the base of the brain Protected by a bony structure called the sella turcica The optic chiasm is located just above the pituitary gland  Carries visual information to the brain for interpretation  Two lobes Anterior lobe Posterior lobe Pituitary Gland Glands

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Anterior Lobe Growth hormone Prolactin Adrenocorticotropic Thyroid-stimulating Follicle-stimulating Luteinizing Stimulates milk production Stimulates the adrenal cortex to release its hormones Stimulates the thyroid gland to release its hormones Females: stimulates estrogen production and maturation of the ova Males: stimulates sperm production Females: stimulates ovulation and estrogen production Males: stimulates testosterone production Pituitary Gland (cont.) Stimulates increase in size of muscles and bones

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Posterior Lobe Antidiuretic hormone (ADH) Oxytocin Stimulates the kidneys to conserve water Females: causes contraction of the uterus and ejection of breast milk Males: stimulates contraction of the prostate and vas deferens during sexual arousal Pituitary Gland (cont.)

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Apply Your Knowledge Match the following: ___ Stored in posterior pituitaryA. Follicle-stimulating hormone ___ Milk productionB. Prolactin ___ Produced by hypothalmusC. Luteinizing hormone ___ Stimulates sperm production D. ADH ___ Maturation of ova E. Oxytocin ___ Stimulates ovulation ___ Conservation of water ___ Production of testosterone ___ Contraction of uterus E D B D, E C A A C ANSWER: Super!

© 2009 The McGraw-Hill Companies, Inc. All rights reserved T 3 T 4 Thyroid Gland and Parathyroid Glands Thyroid Gland  Located below the larynx  Divided into follicles that store some of the hormones Major hormones Stimulate protein synthesis and increase cellular energy production Lowers blood calcium levels by activating osteoblasts that build new bone tissue Glands

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Thyroid Gland and Parathyroid Glands (cont.)  Parathyroid glands Four located on the posterior surface of the thyroid gland Secrete parathyroid hormone (PTH)  Agonist to calcitonin by raising blood calcium levels through activation of osetoclasts (dissolve bone) As bone dissolves, calcium levels in blood increase Glands

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Apply Your Knowledge True or False: __ Thyroid hormones stimulate protein synthesis. __ The thyroid gland does not store hormones. __ PTH activates osteoblasts. __ Calcitonin increases cellular energy production. __ The four parathyroid glands are located on the thyroid gland. __ Calcitonin lowers blood calcium levels. F F F T T T ANSWER: PTH activates osteoclasts. Thyroid hormone increases cellular energy production. Thyroid follicles store some hormones.

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Adrenal Glands  Located on top of each kidney  Divided into the adrenal medulla and adrenal cortex  Adrenal medulla Central portion Hormones  Epinephrine  Norepinephrine  Same effects as sympathetic nervous system Glands

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Adrenal Glands (cont.)  Adrenal cortex Outermost portion Secretes many hormones, but main ones are  Aldosterone Stimulates body to retain sodium and water Important in maintaining BP  Cortisol Released when stressed Decreases protein synthesis, resulting in slowed tissue repair Decreases inflammation

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Apply Your Knowledge Match the following: ____ Adrenal medullaA. Cortisol ____ Sodium retentionB. Epinephrine ____ Decreases inflammationC. Aldosterone ____ Sympathetic effectsD. Norepinephrine ____ Maintains blood pressure ____ Released during stress ____ Adrenal cortex A, C B, D A C A C ANSWER: Excellent!

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Pancreas  Located behind the stomach  Both exocrine gland and endocrine gland Exocrine – secretes digestive enzymes into a duct leading to the small intestine Endocrine – secretes hormones into bloodstream Glands

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Pancreas (cont.)  Islets of Langerhans secrete hormones into bloodstream Alpha cells secrete glucagon Beta cells secrete insulin Blood glucose concentrations Protein synthesis Blood glucose concentrations Protein synthesis

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Apply Your Knowledge What are the effects of insulin and glucagon? ANSWER: Insulin decreases blood glucose concentration and increases protein synthesis. Glucagon does just the opposite. It increases blood glucose and decreases protein synthesis. Yippee !

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Other Hormone-Producing Organs  Pineal body Small gland Located between cerebral hemispheres Melatonin  Regulates circadian rhythms  May play a role in onset of puberty  Thymus gland Located between lungs Thymosin  Promotes production of T lymphocytes Glands

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Other Hormone-Producing Organs (cont.)  The gonads Ovaries  Estrogen  Progesterone Testes  Testosterone  Stomach Gastrin  Small intestine Secretin Cholecystokinin  Heart Atrial natriuretic peptide – regulates BP  Kidneys Erythropoietin – stimulates blood cell production Glands

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Back

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Apply Your Knowledge Match the following: ___ Between lungsA. Pineal body ___ MelatoninB. Heart ___ Estrogen/testosteroneC. Kidneys ___ GastrinD. Thymus gland ___ SecretinE. Small intestine ___ ErythropoietinF. Stomach ___ Atrial natriuetic peptideG. Gonads ___ Thymosin ___ Cholecystokinin C E F G A E D B D ANSWER:

© 2009 The McGraw-Hill Companies, Inc. All rights reserved The Stress Response  Stressor Any stimulus that produces stress Types  Physical factors  Psychological factors  Positive stimuli

© 2009 The McGraw-Hill Companies, Inc. All rights reserved The Stress Response (cont.)  Physiologic response to stress caused by hormone release General stress syndrome  Increased heart rate, respiratory rate, and BP  Increase in glucose and fatty acids in blood, which leads to weight loss  Increase in cortisol if stress prolonged Decreased body repair Susceptibility to illness

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Apply Your Knowledge Match the following: ___ Extreme heatA. Physical stress ___ Death of friendB. Psychological stress ___ Fractured legC. Positive stimulus ___ Wedding ___ Exam ___ Hearing an explosion nearby ___ “A” on an exam ___ Flu ___ Car stolen B B B A A C B C A ANSWER:

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Common Diseases and Disorders Disease/DisorderDescription AcromegalyToo much growth hormone produced in adults; enlargement of bones and thickened skin Addison’s diseaseAdrenal gland fails to produce enough corticosteroids CretinismExtreme form of hypothyroidism present prior to or soon after birth Cushing’s diseaseHypercortisolism; over-production of cortisol Diabetes insipidusKidneys fail to reabsorb water, resulting in excessive urination; hyposecretion of ADH

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Common Diseases and Disorders (cont.) Disease/DisorderDescription Diabetes mellitus Type I Type II Gestational Chronic disease characterized by elevated blood glucose levels Insulin-dependent diabetes mellitus; usually develops in childhood Noninsulin-dependent diabetes mellitus; primarily in adults but increased incidence in teens Occurs during pregnancy; usually temporary DwarfismToo little growth hormone (somatotropin) produced during childhood

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Common Diseases and Disorders (cont.) Disease/DisorderDescription GigantismToo much growth hormone produced during childhood GoiterEnlargement of thyroid gland, causing swelling in neck; deficiency of iodine in diet Grave’s diseaseHyperthyroidism; antibodies attach to thyroid gland, causing it to produce too much thyroid hormone MyxedemaThyroid gland produces inadequate amounts of thyroid hormone; common in females over 50

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Apply Your Knowledge True or False: ___ Acromegaly develops as a result of too much growth hormone in a child. ___ In diabetes insipidus, the kidneys fail to reabsorb water. ___ Too little growth hormone in childhood results in dwarfism. ___ Myxedema is the result of hyperthyroidism. ___ Addison’s disease is the result of too little corticosteroid. ___ Cushing’s disease is the result of too little ACTH. ___ Cretinism is an extreme form of hyperthyroidism present at birth. F T T T F F ANSWER: F hypothyroidism too much ACTH hypothyroidism in an adult Correct!

© 2009 The McGraw-Hill Companies, Inc. All rights reserved In Summary  The organs of the endocrine system secrete hormones directly into blood and other body fluids.  Hormones secreted by the endocrine system control the functions of other cells.  Endocrine organs Hypothalamus Pituitary gland Thyroid gland Parathyroid glands Adrenal glands Pancreas Pineal body Thymus gland Gonads, stomach small intestine, heart, kidneys

© 2009 The McGraw-Hill Companies, Inc. All rights reserved Its not stress that kills us, it is our reaction to it. ~ Hans Selye