KINESIOL 1YY3 Lecture 4: The Endocrine System
3 Sep 2018
School
Department
Course
Professor
Document Summary
Secrete products into ducts that empty into body cavities/surfaces;ie sweat, mucous glands; anything that opens to outside. Secrete products (hormones) into interstitial space (around a cell)/bloodstream. Pituitary, thyroid, parathyroid, adrenal, pineal (blue labels above) Other organs secrete hormones as a 2nd function. Hypothalamus, thymus, pancreas, ovaries, testes, kidneys, stomach, liver, small intestine, skin, heart, adipose tissue & placenta (red labels above) Hormones only affect target cells w specific membrane proteins called receptors. Work like a lock & key method; float around looking around for a specific matching receptor. Once hormone binds, it may do a different job in the cell as well; 1 hormone can have more than 1 function depending on where they bind. In sm, they may cause vasodilation or vasoconstriction; in cardiac, can change stroke volume & pumping; in skeletal muscle, can cause metabolic breakdowns of fats into fuels. Excess hormone, may produce a decrease in # of receptors leads to decreased sensitivity.
