BIOL 1344 Lecture 11Outline of Last Lecture I. Endocrine System CommunicationA. Action and Graded PotentialsB. Chemical CommunicationII. Endocrine System ReleasesA. NeurotransmitterB. Neuro-hormonesC. Hormones III. Functions of the Endocrine System A. HomeostasisB. ReproductionOutline of Current Lecture IV. Functions of the Endocrine SystemA. Growth and MetabolismB. DigestionV. Endocrine Glands in the Body VI. Classification of Hormones Current LectureGrowth and metabolism are additional functions of the endocrine system. It emits the growth hormone somatotropin which is responsible for physical growth and height. If there is too little of this hormone this can cause dwarfism. If there is too much, this causes gigantism. If there is too much in an adult, this can result in acromegaly which is continued growth of bones into adulthood. Its metabolic effects are shown in the emission of insulin and glucagon. Insulin causes glucose metabolism. Glucose can either be oxidized resulting in water, carbon dioxide, and ATP, or it can be stored as glycogen or lipids (fats). The process of glucose being stored as lipids is irreversible so a person must burn off the fats through aerobic exercise in order to reduce the level of lipids.Other metabolic effects include the thyroid hormones T3 and T4 which control basal metabolic rate (BMR) which is normally around 39 kcal/hr/square meter of body surface. Hyperthyroidism is a condition in which the thyroid is too active and the body loses too much heat and energy. These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Blood glucose levels – after eating, this results in hyperglycemia, over a little bit of time, insulin lowers this level into normoglycemia (euglycemia). When a person hasn’t eaten for a while, this is hypoglycemia. Glucagon is needed to restore conditions. So there must be a balance of these two hormones, insulin being a hypoglycemic hormone and glucagon being a hyperglycemic hormone. Digestion – hormones which aid digestion are cholecystokinin (CCK) which is released in the duodenum and inhibits appetite. Bulimia nervosa can result from a lack of this hormone. There is also pancreatic secretion which is rich in bile and controls emulsification of fats. Ghrelin is a hormone which is released in the stomach and increases appetite. Endocrine Glands 1. Hypothalamus: synthesizes ADH and oxytocin, thryotropin release hormone (TRH), gonadotropin release hormone (GRH), corticotropin release hormone 2. Epithalamus: releases melatonin through the pineal gland, melatonin is released in darkness and is sleep inducing. It also releases suprachiasmatic nucleus (SCN) which controls the biological clock and circadian rhythm. 3. Hypophysis / Pituitary: The anterior lobe (adenohypophysis) synthesizes and releases 7 hormones. a. Prolactin: milk secretionb. Somatotropin: physical growthc. Thyrotropin/ Thyroid Stimulating Hormone (TSH)d. Corticotropin/ Adrenocorticotropic Hormone ACTHe. Follicle Stimulating Hormone (FSH): gonadotropinf. Luteinizing Hormone (LH): gonadotroping. Melanocyte Stimulating Hormones (MSH): melanocytes which synthesis melanin which factors into skin color. If melanin is missing the person has albinism. If melanocytes are missing, the person suffers from vitiligo which creates patchy areas of whiter skin.The posterior lobe (neurohypophysis) synthesizes and releases 2 hormones.a. ADH: water reabsorptionb. Oxytocin: a bonding hormone4. Thyroid: T3 (tri-iodo-thyronine) and T4 (tetra-iodo-thyronine) both are calorigenic and control heat production and BMR control. They are also important in mental, gonadal, and physical development. The thyroid also releases calcitonin which causes hypocalcemia or low calcium. It turns blood calcium into bone calcium. 5. Parathyroid: parathyroid hormone (PTH) causes hypercalcemia or high calcium levels by turning bone calcium into blood calcium so this along with calcitonin maintains a healthycalcium level in the body.6. Adrenals: adrenal cortex releases cortisol (an anti-inflammatory), aldosterone (controls sodium retention), and DHEA (testosterone). The adrenal medulla releases epinephrine, norepinephrine, and dopamine.7. Pancreas: beta cells release insulin. Alpha-cells release glucagon.8. Other glands in the body include the testes, ovaries, skin liver, kidneys, thymus, and heart.Classification of HormonesProteins: made up of amino acidsSteroids: cholesterol precursor, androgens, estrogensAmines: adrenal medullary hormonesProstaglandins: eicosanoids- have 20 carbon