Tpic 12: Endcrine System Functin: Grup f glands that prduces regulatry chemicals ( ) Hrmnes: Chemical messengers released directly int the bldstream that regulate: *May have wide-spread effects r nly affect certain cells knwn as cells that cntain receptrs that respnd t specific hrmnes Tw Main Categries f Hrmnes Prtein hrmnes: includes all hrmnes except thse f the crtex and Lipid hrmnes: includes hrmnes prduced by the crtex and Mst are sterids Hrmne names end in - (ex: ) Endcrine Glands Hypthalamus Secretes releasing hrmnes ( ) Secretes inhibiting hrmnes ( ) Hrmnes prduced: Antidiuretic hrmne (ADH): Oxytcin: Pituitary Cnsidered the since it released hrmnes that affect the wrking f ther glands The pituitary is cntrlled by the Hrmnes prduced and released by pituitary: Grwth hrmne (GH) Thyrid stimulating hrmne (TSH)
Adrencrtictrpic hrmne (ACTH): Prlactin (PRL): Fllicle stimulating hrmne (FSH): Luteinizing hrmne (LH): Endrphins: Hrmnes released by pituitary Antidiuretic hrmne (ADH) Oxytcin Disrders f the Pituitary: Gigantism: pituitary tumrs that develps early in childhd and causes excessive prductin f hrmne Acrmegaly: caused by an veractive grwth hrmne prducing cells in an adult May have widespread bdy system effects Dwarfism: caused by a deficiency in grwth hrmne Pineal Hrmne prduced and released: Melatnin: Thyrid Hrmnes prduced and released: Calcitnin: Thyrxin (T4): Triidthyrxin (T3) Disrders f the Thyrid: Giter: enlargements f the thyrid gland due t a lack f in the diet Hypthyridism: f the thyrid Infantile hypthyridism (cretinism): failure f the thyrid gland t frm in fetal develpment
Myxedema: results frm the thyrid s underactivity in adulthd Hyperthyridism: f the thyrid Graves disease: symptms include Thyrid strm: hyperthyridism that ccurs suddenly Thyriditis: inflammatin f the thyrid (ex: ) Parathyrid Hrmne prduced and released: Parathyrid hrmne: prmtes released frm bne tissue (wrks with t regulate bld calcium levels) Disrders f the Parathyrid Tetany: prductin f parathyrid hrmne causes muscle cntractin due t lw bld levels Thymus Hrmne prduced and released: Thymsin: assists in immunity thrugh the develpment f cells Pancreas (Islets f Langerhans) Hrmnes prduced and released: Insulin: Glucagn: Disrders f the Pancreas Hyperglycemia (Diabetes mellitus): excess glucse in the bld caused by an inability f the islet cells t prduce enugh insulin Type 1 (Juvenile diabetes): appears befre the age f, caused by an autimmune destructin f insulin prducing cells Type 2 (adult nset): caused by weight gain and can be cntrlled by weight gain and exercise Gestatinal: ccurs during when mm cannt prduce enugh fr bth mther and child Hypglycemia: lw bld glucse levels caused by:
Can d damage t cells especially brain cells because they are nt getting enugh glucse Adrenal glands Hrmnes prduced and released by the adrenal : Epinephrine (adrenaline) Nrepinephrine (nradrenaline) Hrmnes prduced and released by the adrenal : Gluccrticids: maintains the bdy s reserve by stimulating the liver t cnvert int and suppresses the inflammatry respnse (ex: ) Mineralcrticids: regulates balance (imprtant fr the kidneys t regulate bld pressure) ex: Sex hrmnes: andrgens ( ) and estrgen ( ) Disrders f the Adrenal Crtex Addisn disease: muscle atrphy ( ), weakness, change in skin pigmentatin due t f crtisl Cushing syndrme: besity, muscle weakness and bne lss due t f crtisl Gnads Ovaries Lcatin: Hrmnes prduced and released: Estrgen: Prgesterne: Testes Lcatin: Hrmnes prduced and released: Teststerne: Other Hrmne Prducing Tissues Stmach and small intestine secrete hrmnes fr digestin Kidneys secrete t stimulate red bld cell prductin Atria secrete t increase sdium excretin t lwer bld pressure Placenta prduces hrmnes during pregnancy Prstaglandins: hrmnes made by mst bdy tissues Are prduced, act and are rapidly inactivated in r clse t their sites f rigin
Hw d Hrmnes Maintain Hmestasis? Feedback mechanisms: hmestasis mechanism that helps keep a variable clse t a particular value r set pint A sensr detects a change in the internal r external envirnment and alerts a cntrl center The cntrl center activates the effectr The effectr reverses the change and brings cnditins back t nrmal Negative feedback: A self-regulating mechanism that decreases the actin r level f a particular substance in rder t maintain hmestasis Questin: In the space belw, pick tw hrmnes that we have discussed and describe hw they wrk tgether in a negative feedback mechanism t maintain hmestasis. Psitive Feedback: Bdy s way f further enhancing a respnse t a stimulus Ex: Questin: What are sme differences between the endcrine and nervus systems? Endcrine System Nervus System