Physiology 2130 Lecture Notes - Lecture 3: Electrochemical Gradient, Membrane Potential, Cell Membrane

• School: Western University
• Department: Physiology
• Course: Physiology 2130
• Professor: Christine Bell

Document Summary

The cell membrane separates the intracellular environment from the extracellular environment. It provides 2 way traffic for nutrients and waste needed to sustain metabolism, while it prevents passage of other substances. Movement of molecules from an area of high concentration to an area of low concentration: until no more concentration gradient and net movement is zero. Electrically charged molecules tend to move toward opposite charge (positive ions toward negative ions) and will stop moving when molecules reach electrochemical equilibrium. Lipid solu(cid:271)le su(cid:271)sta(cid:374)(cid:272)es (cid:272)a(cid:374) (cid:272)(cid:396)oss (cid:396)ight th(cid:396)ough the (cid:272)ell (cid:373)e(cid:373)(cid:271)(cid:396)a(cid:374)e (o , co , fatt(cid:455) a(cid:272)ids, so(cid:373)e hormones) while water soluble have a tougher time: water soluble may cross through special protein channels/pores (na+ and k+) A particular molecule binds to special protein channels in the plasma membrane and is released on the far side of the membrane. Moves the molecule up their concentration gradient from low concentration to high concentration.