HPEX 250: Module 16: The Endocrine SystemSection 1: Anatomy and Physiology- Lesson 1: Endocrine System Overviewo Endocrinology Endocrine- Secreting substances internally Endocrinology- The study of the endocrine glands Endo-- Within -Crine and crin/o- To secrete Glands- Aden/oo Endocrine System Organs Pituitary Glands- (pituitar/o) Pineal Gland Thyroid Gland- (thyroid/o & thyr/o) Parathyroid- (parathyroid/o) Thymus Adrenal Glands Pancreas- Pancreat/oo Endocrine vs. Exocrine Endocrine- Ductless- Secrete hormones into the bloodstream through a glandular membrane Exocrine- Deliver their secretions through a duct- Exo- means out and away- Sweat glands are exocrine glands- Produce a transparent watery liquid that travels through a duct to the surface of the skino Categories of hormones Protein- Hormone formed from amino acids  Steroid- Hormone formed from the lipid cholesterolo Target Tissue Specific tissues that hormones work by affectingo Hormone Function Hormones interact with target tissues by binding to receptors on or within the surface of the tissues cells Receptors- Enable the tissue to recognize and respond to specific hormoneso Erythropoietin Substance that stimulates the production of red blood cells- Lesson 3: Anterior Pituitary Glando Pituitary Gland Pituitar/o Supplies hormones that effect almost every bodily function AKA = master gland and hypophysis cerebri Small, pea-shaped gland attached to the undersurface of the hypothalamus in a depression of the skull called sella turcica Consists of two major lobes- Anterior Lobeo Adenohypophysiso Upward extension of the pharynx composed of glandular tissue- Posterior Lobeo Neurohypophysiso Downward projection of the brain composed of nervous tissueo Hypothalamus in the Pituitary Gland Hypothalamus- Activates, integrates and controls the endocrine processes, somatic functions and peripheral autonomic nervous system- Exerts an important function on the pituitary glando It targets the organo It controls the secretion of the anterior pituitary lobe by secreting release-inhibiting hormones- Produces hormones that transported to the posterior pituitary lobe o Where they can be stored until neededo Growth Hormone Somatotropin Affects the growth of the skeletal muscles and the long bones of the body Promotes the synthesis of proteins, preforms cell repairs, and helps maintain blood glucose levelso Prolactin-Releasing (Lactogenic) Hormone Another hormone secreted by the anterior pituitary lobe Stimulates the growth and development of the mammary glands Causes each mammary gland in the breast to produce milk after childbirtho Thyroid-Stimulating Hormone Thyrotropin Substance secreted by the anterior pituitary lobe Controls the release of the thyroid hormone Stimulates that growth and function of the thyroid glando ACTH Adrenocorticotropic Hormone Target Tissue Outer portion of the adrenal gland- Adrenal cortex -tropic = turning toward or changing Stimulates the growth of the adrenal cortex and causes it to secrete 3 steroid hormones, including cortisolo FSH, LH, MSH Gonadotropic Hormones- Anterior Pituitary Lobe has 2 to target the gonads or the sex glandso Follicle-stimulating hormone Stimulates the growth of the ova- Eggs in females- Sperm in maleso Luteinizing Hormone Causes the secretion of sex hormone in men and women - Estrogen- Progesterone- Testosterone Stimulates the process of ovulation Melanocyte-Stimulating Hormone- Affects the skin’s pigment-producing cells- Posterior Pituitary Glands and Pineal Glandso ADH, Oxytocin Antidiuretic Hormone- Decreases the production of urine by increasing the reabsorption of water by the renal tubules- Vasopressino Synthetic ADHo Used in the treatment of diabetes insipidus Oxytocin- Serves an important function in women during the process of labor and delivery- Stimulates the smooth muscle of the uterus to contract- Responsible for the release (letdown) of milk from the mammary glands in response to an infant’s suckling o Pineal Gland Housed in the cranial cavity Cone-shaped structure Melatonin- Only hormone secreted by the into the blood stream by the pineal gland- Lesson 5: The Thyroid, Parathyroid, and Thymus Glandso Thyroid Gland Largest endocrine gland in the body Located in the anterior neck and the front and sides of the trachea- Just below the thyroid cartilage Consists of a right and left lobe connected in the middle by a narrow strip of tissue called isthmuso Thyroid Hormones Triiodothyronine- T3 Tetraiodothyronine- Thyroxine- T4 Synthesized from iodine  Increase metabolic rate o Parathyroid Gland Tiny structures embedded in the posterior lobes of the thyroid glando Thymus Gland Lies in the mediastinum, beneath the sternum Organ of the lymphatic system Secretes a hormone called thymosin- Stimulates the development of the immune system and the production of lymphocytes Relatively much larger in children than adults- Lesson 6: Adrenal Glandso Adrenal Glands AKA = Suprarenal Glands Consists of two regions- Outer portion (Adrenal Cortex)o Secretes 3 types of steroid hormones (Corticosteroid) Mineralocorticoid- Produced in the outer layer- AKA Zone- Regulate the amount of mineral salts in the blood- Aldosteroneo Targets the kidney to increase the amount of sodium and decrease the amount of potassium in the blood Glucocorticoid- Hormone secreted from cells in the middle layerof the adrenal cortex- Main is cortisol (hydrocortisone)- Inner part (Adrenal Medulla)o Secretes 2 important nonsteroidal hormones Epinephrine- Adrenaline Norepinephrine- Noradrenaline Help the body respond to stress by elevating blood pressure, increasing heart rate, dilating the bronchial passages, increasing the respiratory rate, and making more glucose available to the cells.- Lesson 6: Pancreaso Pancreas Pancreat/o A long gland that stretches across the posterior wall of the upper abdomen Composed of both endocrine and exocrine tissue Is an exocrine gland- Aids in digestion of food Islets of Langerhans- Cluster of cells, scattered throughout the pancreas- Form the endocrine portion of the gland- Two types of cellso Alpha cells Secrete the hormone glucagon- Antagonizes and opposes the effects of insulin - When blood sugar levels are low glucagon stimulates the conversion of glycogen to