The Human BodyWhat is it How does it

The Human Body…What is it? How does it work? Let’s operate and find out! Chapter 15: Endocrine System Learning Objectives: 1) Describe the major endocrine organs, their body locations, and associated hormones. 2) Describe how hormones are chemically classified. 3) Explain the relationship between hormones and target tissues/ cells. Homework assignment: Read Chap 15 (pages 533 – 564). Use your “Interactive Physiology” CD-ROM to study/ review the endocrine system (Select “Endocrine” on the Main Menu of the CD-ROM and go through the various modules).

PREDICT • What’s does the “endocrine system” refer to? What do you think?

BRAINSTORMING • Activity to be presented in class

Major Endocrine Organs, page 533

PARTNER ACTIVITY: WHAT DO THE ENDOCRINE ORGANS DO? Instructions: Using your textbook or other resource, match the endocrine organ with its general description. Estimated Time: 8 -10 minutes 1. pineal gland a. Sits near base of the brain; secretes hormones regulating homeostasis; it is functionally connected to the hypothalamus. 2. adrenal glands b. An organ in the digestive and endocrine systems of vertebrates; produces insulin, and glucagon. 3. pituitary gland c. controlled by the hypothalamus and pituitary; produces thyroxine (T 4) and triiodothyronine (T 3) which regulate the rate of metabolism and affect the growth and rate of function of many other systems 4. thymus gland d. links the nervous system to the endocrine system via the pituitary gland ; controls body temperature, hunger, thirst 5. pancreas e. sit on top of the kidneys; chiefly responsible for regulating the stress response through the synthesis of cortisol and adrenaline. 6. hypothalamus f. maintains the body's calcium level so that the nervous and muscular systems can function properly; located in neck 7. Thyroid gland g. located in the upper portion of the chest cavity just behind the sternum; stimulates the production of certain infection-fighting cells. 8. Parathyroid glands h. small endocrine gland in the brain; produces a hormone that may modulate wake/sleep patterns called melatonin

A Closer Look at Hormones • Hormones – __________ released into the blood to be transported throughout the body • They are chemically classified as either amino acid based or _____ • _____ bind to cellular receptors and initiate a response within a matter of time (seconds, minutes, hours or days) Hormones influence the activity of only certain tissue cells referred to as target cells – act like two puzzle pieces made for each other. Hormones affect target cells by altering cell activity – either increase or decrease normal cellular processes. Target cells have special receptor areas.

Hormones Continued • Hormones produce one or more of the following cellular changes in _______ cells: – – – Alter ____ membrane permeability Stimulate ____ synthesis Activate or deactivate _______ systems Induce secretory activity Stimulate _______ Animation – target cells. In order for a target cell to respond to a hormone, the cell must have specific protein receptors on its plasma membrane or interior to which that hormone can bind.

A Closer Look at the Endocrine Organs Pituitary gland or ______ – two-lobed organ that secretes at least eight major hormones. Pituitary gland hormonally influences many body organs including the thyroid, adrenal glands, reproductive system, kidneys, and ______ Basic anatomy: ________ (with hypothalamic-hypophyseal nerve bundle) _________ – posterior lobe (neural tissue) and the infundibulum; receives, stores, and releases hormones from the hypothalamus _________ – anterior lobe, made up of glandular tissue; synthesizes and secretes a number of hormones

Hormones dumped into bloodstream ______ or ____

Pituitary continued Posterior lobe hormones: - _______ - Antidiuretic Hormone (___) or ______ Anterior lobe hormones: Tropins – - Thyroid-stimulating Hormone (___) hormones that - Adrenocorticotropic Hormone (_____) regulate the secretory - Follicle-stimulating Hormone (___) action of other endocrine - Luteinizing Hormone (___) glands - Growth Hormone (___) - Prolactin (___)

What do these hormones do? Instructions: Working individually, take a few minutes to investigate more about each of the hormones. For each hormone, answer the question, “What does this hormone do? ” Write this information in your notes. Estimated time: 7 -8 minutes. 1. Oxytocin (pg 545) 2. ADH (pg 545) 3. TSH (pg 544) 4. ACTH (pg 544) 5. FSH (pg 544) 6. LH (pg 544) 7. GH (pg 542) 8. PRL (pg 544)

Small Group Activity – Pituitary Initiated Disorders Estimated Time: 10 minutes • Form a small group of 4 people. • Obtain a “Pituitary Disorders” packet. • Put yourself in the role of a medical investigator. Each card in the packet represents a disease/symptoms. Can you name the diseases/ syndromes? • You may use your textbook as a resource (NOTE: Table 15. 1 Pituitary Hormones pages 546 – 547 may be helpful)

Endocrine Organs Continued Thyroid Gland – anterior neck; on the _____; just inferior to the _______. Two lobes connected by _______. Composed of spherical follicles containing _______. The walls of the follicles are made up of squamous epithelial cells which produce a glycoprotein called thyroglobulin. Parafollicular cells produce calcitonin. Remember that TSH from pituitary acts on the thyroid.

Practice, page 548 Instructions: Practice labeling & learning the anatomy of the thyroid on the handout sheet.

Thyroid continued The Thyroid secretes: • Thyroid Hormone (____) which is actually two iodinecontaining amine hormones, thyroxine (T 4) and triiodothyronine (T 3). • T 4 – is secreted from the thyroid _____ • TH affects virtually every cell in the body except for the adult _____, _______, and the thyroid gland itself. • Calcitonin – a hormone that regulates blood ____ levels (secreted from the parafollicular cells) Take a moment to review the effects of T 3 and T 4 in Table 15. 2, page 549.

Thyroid Disorders • _____thyrodism or myxedema – symptoms include low metabolic rate, feeling cold, constipation, mental sluggishness, possibly goiter • ______thyroidism – too much TH; causes elevated metabolic rate, sweating, rapid irregular heartbeat, and possibly protruding eyeballs (Graves Disease)

Parathyroid glands, page 552 • Tiny glands embedded in the posterior aspect of the thyroid Side Note: How many parathyroid glands can you see in this picture?

Parathyroid continued • Secrete parathormone (PTH) which regulates calcium balance in the blood via bone, intestines, and kidneys • Calcium key for transmission of _______, muscle ____, and blood ______.

Parathyroid Gland Disorders • Hyperparathyroidism – rare (usually the result of a tumor); calcium is ______ ______. Calcium deposits may also form in soft tissues throughout the body. • Hypoparathyroidism – loss of ____, muscle ______, and _____. Untreated symptoms lead to respiratory paralysis and death.

Adrenal Glands, page 554 (also known as the Suprarenal Glands) • Pyramid-shaped organs sitting atop the kidneys • Produces well over 2 dozen steroid hormones collectively known as ___________ mineralocorticoids glucocorticoids gonadocorticoids epinephrine

Adrenal Gland Hormones, pg 555 1) ______corticoids (chiefly _____ which maintains Na+ balance by reducing excretion of sodium from the body and stimulates reabsorption of Na+ by the kidneys; affects blood pressure) 2) _____corticoids(chiefly _____ which helps the body resist stress by keeping blood sugar levels relatively constant and maintaining blood volume and preventing water shift into tissue) Cortisol provokes: – Formation of glucose from noncarbohydrates – Rises in blood _______, fatty acids, and amino acids

Adrenocortical Hormones continued 3) ____corticoids (chiefly _____. Most gonadocorticoids secreted are androgens (male sex hormones); Most important one is testosterone. Androgens contribute to: – The onset of ____ – The appearance of secondary ____ characteristics – Sex drive 4) ______ (more potent stimulator of the heart and metabolic activities) and ______ (more influential on peripheral vasoconstriction and blood pressure) Secretion of these hormones causes: – Blood glucose levels to ____ – Blood vessels to _______ – The heart to beat ____ – Blood to be diverted to the brain, heart, and skeletal muscle

Adrenal Disorders • ____ syndrome – glucocorticoid excess (may be caused by an ACTHreleasing pituitary tumor) • _____ disease – deficits in both glococoticoids and mineralocorticoids; victims loose weight, glucose and Na+ levels drop while K+ rise resulting in severe dehydration

Pancreas, page 560 • A triangular gland, which has both _______ and _______ cells, located behind the stomach • ______ cells produce an enzyme-rich juice used for digestion (exocrine product) Pancreatic islets (islets of Langerhans) produce hormones (endocrine products). The islets contain two major cell types: Alpha ( ) cells that produce glucagon (hyperglycemic agent) Beta ( ) cells that produce insulin (hypoglycemic agent)

Glucagon One molecule of this hormone can cause the release of 100 million glucose molecules into the blood! • A 29 -amino-acid polypeptide hormone that is a potent _______glycemic agent • Its major target is the _____, where it promotes: – The breakdown of glycogen to ______ – Synthesis of glucose from ______ acid and noncarbohydrates – Release of glucose to the blood from liver cells

Insulin • A ___-amino-acid protein consisting of two amino acid chains linked by disulfide bonds • Insulin: – _______ blood glucose levels – Enhances transport of glucose into ____ cells – Counters metabolic activity that would enhance blood glucose levels – Also influences _____ and ___ metabolism

Blood Glucose Regulation • The hyperglycemic effects of glucagon and the hypoglycemic effects of insulin Side Note: Glucagon and insulin do opposite tasks; the counteroppose one another

Pancreas Disorders _____ Mellitus (DM) • Results from hyposecretion or hypoactivity of _____ • The three cardinal signs of DM are: – Polyuria – – Polydipsia – – Polyphagia – Hyperinsulinism – excessive insulin secretion, resulting in hypoglycemia

Pineal Gland, page 563 • Small gland hanging from the ______ of the third ventricle of the brain • Secretory product is _____ • Melatonin is involved with: – Day/night cycles – Physiological processes that show rhythmic variations (body ____, ______, and appetite)

Thymus Gland, page 564 • Lobulated gland located deep to the ____ in the thorax • Major hormonal products are thymopoietins and thymosins • These hormones are essential for the development of the __ _____ (T cells) of the immune system

Chapter Review As a result of the preceding information you should now be equipped to answer the following questions. 1. The pituitary gland is connected to the hypothalamus of the brain via a narrow connected stalk-like area called the _______? 2. The anterior of the pituitary is also known as the _____? 3. The posterior of the pituitary secretes the hormones _____ and ______? 4. What does ADH control? 5. GH deficiency in children results in slowed bone growth and a condition known as _______?

Chapter Review continued 6. What is the median tissue mass that connects the two lobes of the thyroid? 7. What two iodine-containing amine hormones actually make up TH? 8. Severe hypothryoidism in infants results in mental retardation, short/ disporportionate body size, and a thick tongue/neck. This condition is known as ______? 9. A hyperthyroid condition resulting in bulging eyes, elevated heartbeat, nervousness, and unexplained weight loss?

Chapter Review continued 10. The beta cells of the pancreas produce what hormone? 11. What does the hormone aldoesterone do? 12. What is PTH and what does it influence?