BIOL 103 Lecture Notes - Lecture 5: Steroid Hormone Receptor, Endocrine System, Thyroid
25 Nov 2016
School
Department
Course
Professor
Document Summary
Respond to changes in external or internal conditions, cells in cns or endocrine system release molecules, produce long term response in tissues and organs. Endocrine system: collection of organs and cells that secrete chemical signals into the bloodstream. Hormone: chemical signal that circulates through body fluids and affects distant target cells. Chemical signals may be very low concentration, but have enormous effect on target cell, relatively long lasting effect when compared to action potentials. Biologists organize diverse chemical signals based on molecule origin and where they act, 6 classes do not coincide with 6 structurally distinct classes of molecules. Autocrine signals act on same cell that secretes them: autocrine = same-separated. Best studied are cytokines, amplify response of a cell to a stimulus, eg: interleukin 2. Synthesized and released by white blood cell (t cell) in course of fighting infection.
