Endocrine System & Stress Response 2024 PDF

The Endocrine System Chapter 9 “Giant of Illinois” Robert Wadlow 1918 - 1940 8ft 11.5 inches Endocrine System The endocrine system consists of glands and “master gland” cells that secrete hormones into the bloodstream. Hormones have a slower & l...

The Endocrine System Chapter 9 “Giant of Illinois” Robert Wadlow 1918 - 1940 8ft 11.5 inches Endocrine System The endocrine system consists of glands and “master gland” cells that secrete hormones into the bloodstream. Hormones have a slower & longer lasting effect on the body. Endocrine System Glands can be : Exocrine Glands Endocrine Glands exo = external, outside endo = internal, within Secrete contents into Release hormones directly ducts which are then into bloodOUR stream; kept secreted outside the body FOCUS inside the body Hormones Hormones are chemicals substances secreted by glands to affect the functions of another cell (target cells) Target cells have receptors (made of proteins or glycoproteins) with binding sites for a specific hormone. Hormones Tropic Hormones affect other endocrine glands causing them to release their hormones E.g. FSH, released by pituitary gland, causes ovaries to release estrogen Pituitary ENDO “master gland” b/c it controls the secretion of hormones posterior pituitary DOES NOT make hormones; it stores and releases; it is part of the nervous system Anterior vs. Posterior Pituitary Hormones  Anterior vs. Posterior Pituitary Hormones Growth hormone (aka somatotropin) promotes cell division, protein synthesis, and growth of bone Prolactin stimulates milk production and affects carbohydrate and fat metabolism Melanocyte-stimulating hormone (MSH) stimulates production of melanin, the major body pigment Adrenocorticotropic hormone (ACTH) regulates response to stress; it stimulates the adrenal cortex to secrete glucorcorticoids (e.g. cortisol) which in turn regulate cardiovascular, metabolic, homeostatic, and immunologic functions Thyroid-stimulating hormone (TSH) causes the thyroid gland to make two hormones: triiodothyronine and thyroxine which help control your body's metabolism and are needed for normal growth of the brain Gonadotropins (LH and FSH) Thyroid MUSCULAR INJURIES A goiter is an abnormal enlargement of the thyroid gland. it is often caused by the lack of iodine in diet. Iodine is used to make T3 and T4. without Iodine, pituitary gland keeps producing more TSH which then causes the gland to be enlarged. Food Rich in Iodide The Stress Response Chapter 9.3 (p. 404-407) What is Stress? ▶ In biology, stressors are anything that causes the release of stress hormones. o Physiological (or physical) stressors: stressors that put strain on our body (i.e. cold/hot temperatures, injury, chronic illness, or pain). ▶ Psychological Stressors: situations, individuals, comments, or anything we interpret as negative or threatening (i.e.: exam time is approaching and you haven’t studied, breakup with girl/boyfriend, cyberbullying). ▶ Absolute vs. Relative Stressors Key point- our body treats all types of stress the same Science of Stress (Nat-Geo) http://video.nationalgeographic.com/video/science-stress-sci Short Term Stress aka “Fight or flight Response” hypothalamus receives signal that a stressful situation has presented itself neuron stimulates adrenal glands Adrenal glands secrete Adrenaline (epinephrine), noradrenaline (norepinephrine), and Cortisol  Short Term Stress Ted ED: How Stress affects your body. Effect of cortisol, epinephrine, and norepinephrine on the body: Muscle tension Increased Pupils dilate breathing rate Redirection of blood flow Long Term Stress If our body is chronically (frequently) stressed, it releases: glucocorticoids: increase blood sugar; such as cortisol Mineralocorticoids: increase blood pressure; such as aldosterone gonadocorticoids (small amounts): supplement the hormones produced by the gonads (testes and ovaries) glucocorticoids ★ CRH= corticotropin releasing hormone (i.e. cortisol) ★ ACTH = Adrenocorticotropic hormone mineralocorticoids (i.e. aldosterone) gonadocorticoids Summary: Long Term vs. Short Term Stress released quickly b/c controlled by nervous system i.e. aldosterone i.e. cortisol Immediate impact of Cortisol Cortisol raises blood glucose by promoting breakdown of muscle protein and fat. Both are converted into glucose. blood glucose pancreas releases muscle protein liver converts fat is glucagon (signal is broken & sent protein into converted liver to make to liver glucose to glucose glucose)  Long Term impact of Cortisol Continuous release of CORTISOL can have negative impacts: * Long term stress lowers your level of general health Ted Ed: Stress and Brain Size How does stress cause weight gain? Other factors that can Cortisol Lack of Sleep Caffeine Alcohol CORTISOL Food How do we typically deal with stress? Scenario one: you have an exam tomorrow Scenario two: your parents are “on your back” about grades and university choices Scenario three: share one So? Can stress kill you? In Japan, where long work hours and high-stress jobs are common, so many business people have died from heart attacks and strokes that the phenomenon has been named karoshi, which means “death from overwork.” Seek Support Take time and Accept who you are & Set goals Have Fun know you have value Dealing with stress properly, and prevention is key! Exercise daily Sleep 8 hours Eat well Meditate and Relax