Skip to content
Class Notes

Endocrine System

A comprehensive overview of the endocrine system, covering key glands, hormone functions, and homeostatic mechanisms—ideal for anatomy and physiology students at any stage of their coursework

Preview 4 of 12 pages

See the first 4 pages exactly as they appear in the document.

  1. Page 1
    Read page 1 as text

    UNIT y he © . r' FTES Lndocrine System 1 RE Sf ole a a OU J e La £5 pit. a oy | aloo he endocrine system is approached differently in different courses. Many choose Se SED, - I efor james Ju wisps vey Sate Ay A v homeostatic control mechanisms. However, others prefer to cover it toward the 5 % 2 “@ end of the course, so students have a better grasp of the anatomy and physiology of Ba ; P “R93 other systems. For this reason, we have structured the excreiscs in this unit such that the LBS % unitis largely “standalone,” meaning it can be used with cither approach. aoe 35 Soo 84d . Pre-Lab Exercises - Pre-Lab16-1 KeyTerms ry General Terms <Q ll Primary endocrine organ (gland) A ductless gland that plays a major rolc in ‘maintaining the body's homeostasis through the secretion of hormones into the bloodstream SC omplason tava. Hormone A chemical messenger scceted into the bloodstream by an endocrine (without pre-tab perce; Bland that initiates a change in a target cell 90-120 minutes Target tissue Tissue whose cells contain receptors for a particular hormone ~~ Negativefeedback A homeostatic mechanism in which a deviation in a Estimated Total Lab physiological variable triggers a response that restores the variable to its sct point; Completion Time when the set point is restored, the response decreases (including Pre-Lab Exercises): 130-160 minutes Endocrine Organs Hypothalamus The inferior portion of the diencephalon; releases hormones that stimulate or inhibit the anterior pituitary and two hormones (ADH and oxytocin) stored in the posterior pituitary Anterior pituitary Anterior portion of the pituitary gland; secretes hormones that largely affect other glands Posterior pituitary Posterior portion of the pituitary gland; does not make its own hormones but rather stores ADH and oxytocin produced by the hypothalamus Thyroid gland Gland located in the anteroinferior neck; composed of thyroid follicles that produce thyroid hormone and calcitonin Thyroid follicle Hollow sphere in the thyroid gland that is lined by follicle cells and filled with a material called colloid Parathyroid glands Three to five small glands located on the posterior thyroid gland; secrete parathyroid hormones that maintain calcium ion homeostasis Pineal gland Small gland located in the posterior/superior diencephalon; secretes ‘melatonin in response to decreased light levels

  2. Page 2
    Read page 2 as text

    Thymus A gland located in the superior mediastinum that is the site of T lymphocyte maturation; largest and most active during infancy and childhood when it is actively secreting thymosin and thymopoictin Pancreas Endocrine and exocrine gland that secretes insulin and glucagon from pancreatic islets Pancreaticislet An “island” of cells within the pancreas that secretes hormones such as insulin and glucagon Adrenal cortex Superficial region of the adrenal gland; consists of glandular tissue that sccretes steroid hormones Adrenal medulla The deep region of the adrenal gland that consists of modified sympathetic neurons that secrete epinephrine and norepinephrine in response to sympathetic stimulation Ovaries Female reproductive organs that produce estrogens and progesterone Testes Male reproductive organs that produce testosterone Pre-Lab16-2 Endocrine System Anatomy | Estimated Completion Time: 10 min § Hpi us Infundibulum oy i pl i Y ead Posterior pituitary it Isthmus Larynx Thymus Trachea Parathyroid glands Pancreas Adrenal cortex Adrenal medulla pra > I fe GN Ap 2 - oh Beta cells ncure 16.1 Organs and tissues of the endocrine system.

  3. Page 3
    Read page 3 as text

    wee 16.1 Properties of Hormones Organ that Secretes Hormone the Hormone: Target Tissue(s) Main Effects Posterior pituitary | Collecting and Antidiuretic hormone (made by the papillary ducts of Increased water reabsorption hypothalamus) the kidneys Postcrior pituitary Oxytocin (madcby the | Milk ducts and Milk cjoction; uterine contraction hypothalamus) ues Thyroid-stimulating LL N Production and secretion of thyroid hormone Antcrior pituitary | Thyroid gland hormone; growth of thyroid gland Adrenocorticotropic PE Stimulates secretion of cortisol (and Ema Let] I Tell ireerrseiall division; increases blood glucose (short-term Growth hormone Anterior pituitary | Nearly all body cells | effect only; decreases blood glucose in the long-term), stimulates lipolysis (short-term cffect only) Reticular formation Ca EE rte Thyroxine and Increases metabolic rate and heat triiodothyronine (4 | Thyroidgland | Most body cells production; promotes growth and and T3) development . Decreases concentration of calcium fons in EN Er BC og EEN Increases concentration of calcium ions in . N the blood by stimulating: (1) osteoclasts, (2) Parathyroid hormone pr Hone, Kidneys small | reas absorption of calcium ions from me the intestines, and (3) reabsorption of calcium fons from the kidneys Most body cells, Helps the body adapt to a stressor by cortex | Particularly cells of | triggering gluconcogencsis, lipolysis, release Adrenal the liver, adipocytes, | of amino acids into the blood, decreasing and muscle cells inflammation ‘Cells of the distal | Increases reabsorption of sodium fous (and Aldosterone Adrenal cortex tubules of the water, indirectly) and sccretion of potassium Kidneys ‘and hydrogen ions from the kidneys (continues)

  4. Page 4
    Read page 4 as text

    ate 16.1 Properties of Hormones (cont) Organ that Secretes Hormone the Hormone 0) Main Effects Epinephrine and Adrenal medulla | Most body cdl | Causes the same effects as the sympathetic norepinephrine nervous system CE NC 30 = adipocytes blood glucose . Increases blood glucose through Liver, . PR TE Pe lipolysis Materials and Prep Notes Exercise 16-1 Endocrine System Anatomy In this exercise, your students study the anatomy of the endocrine system. The anatomy in this unit is spread out among a variety of models, which can make this portion of the lab frustrating for students. We have had the best luck ‘with human torso models and head and neck models. Carolina Biological has endocrine plates as well, although my students have commented that they scem to be little more than three-dimensional illustrations. Procedure 1 Model Inventory of the Endocrine System MATERIALS {11 Anatomical models and diagrams of the endocrine system: endocrine system plates; human torsos; pancreas, spleen, and ‘duodenum; head and neck: and fetus for the thymus Exercise 16-2 Endocrine Organ Histology Students examine the microscopic structures of the thyroid gland, adrenal gland, and pancreas in this exercise. The thyroid gland slide is included with the Tissue Types Microscope Slide Set (Carolina Biological #312148), but the pancreas and adrenal gland must be purchased separately. Procedure 1 Examining Endocrine Tissues with Microscopy MATERIALS 1 Microscope slides: thyroid gland, adrenal gland (Carolina Biological #316766), and pancreas (Carolina Biological #315478 [human] or #315442 [mammal] ); one set per group J Light microscopes with three objectives: 1) Colored pencils Exercise 16-3 Time to Trace! Negative Foadback Loops “This exercise allows students to examine endocrine negative feedback loops that play such a critical role in endocrine ‘maintenance of homeostasis. Due to answers to this activity appearing online, this edition features four all new feedback loops. Procedure 1 Tracing Negative Peedback Loops MATERIALS None required

8 more pages in the full document

Unlock it once and it stays in your library, ready to chat with or turn into flashcards.

Unlock the full document

More Biology study materials

See all

Study this document with CramX

Once it is in your library, every tool can work from it.