© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. THE ENDOCRINE SYSTEM Chapter 12

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Introduction Maintains internal environment (homeostasis) Hypothalamus: sends chemical signals to pituitary Endocrine glands –Ductless –Secrete hormones directly into bloodstream

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Introduction (cont’d.)

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. THE FUNCTIONS OF HORMONES

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. THE CLASSIFICATION OF HORMONES

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. The Classification of Hormones Modified amino acids –Epinephrine, oxytocin Proteins –Insulin, growth hormones Steroid –Cortisol, estrogen

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. THE HYPOTHALAMUS OF THE BRAIN

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. THE MAJOR ENDOCRINE GLANDS AND THEIR HORMONES

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. The Anterior Pituitary Gland, Its Hormones, and Some Disorders (cont’d.) GH: cell metabolism and growth –Controlled by two releasing hormones from hypothalamus Thyroid-stimulating hormone (TSH): stimulates thyroid Adrenocorticotropic hormone (ACTH): stimulates adrenal cortex

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. The Anterior Pituitary Gland, Its Hormones, and Some Disorders (cont’d.) Melanocyte-stimulating hormone (MSH): stimulates melanocytes Follicle-stimulating hormone (FSH) –Females Stimulates ovarian follicle development –Males Stimulates sperm cell production

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. The Anterior Pituitary Gland, Its Hormones, and Some Disorders (cont’d.) Luteinizing hormone (LH) –Females Stimulates ovulation and progesterone production –Males Testosterone production

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. The Anterior Pituitary Gland, Its Hormones, and Some Disorders (cont’d.) Lactogenic hormone (prolactin): stimulates milk production in females –May cause decrease in male sex hormones

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. The Thyroid Gland, Its Hormones, and Some Disorders Located below larynx on either side of trachea Requires iodine

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. The Thyroid Gland, Its Hormones, and Some Disorders (cont’d.) Hypothyroidism –Cretinism –Lowered metabolic rate –Myxedema

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. The Thyroid Gland, Its Hormones, and Some Disorders (cont’d.) Hyperthyroidism –Elevated metabolism –Graves’ disease Exophthalmia

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. The Parathyroid Glands, Their Hormones, and Some Disorders (cont’d.) Hyperparathyroidism –Breakdown of bone matrix Hypoparathyroidism –Low calcium level in blood

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. The Parathyroid Glands, Their Hormones, and Some Disorders (cont’d.) Position of the parathyroid glands

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. The Adrenal Glands, Their Hormones, and Some Disorders Located on top of each kidney Adrenal medulla: epinephrine and norepinephrine Adrenal cortex: aldosterone, cortisol, androgens

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. The Adrenal Glands, Their Hormones, and Some Disorders (cont’d.) Disorders –Addison’s disease: lack of adrenal cortex hormones –Cushing’s Syndrome: too much adrenal cortex hormones

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. The Thymus Gland and Its Hormone Located behind the sternum Secretes thymosin Important for T-cell production Thymus shrinks as we age

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Animation – Endocrine System Click Here to Play Endocrine System Animation

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Summary Discussed the functions of hormones Classified hormones into their major chemical categories Described how the hypothalamus controls the endocrine system

© 2012 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Summary (cont’d.) Named the major endocrine glands and described the effects of their hormones on the body