PSYC 2012 Lecture Notes - Lecture 5: Cell Membrane, Action Potential, Hydrolysis
Document Summary
Week 3: the action potential & synaptic transmission. Neurons are the main functional cells of the nervous system and communicate by creating and sending electrical signals. Electrical signals are generated by the movement of charge. Charge is carried by ions, which are atoms that gain or lose electrons. Goal: to determine how neurons produce transient electrical signals through the movement of ions through voltage-gated ion channels and how they communicate these electrical changes to other neurons. Diffusion - a major way small particles move. Particles move from areas of high concentration to low concentration. Movement of particles down their concentration gradient (from high to low) does not require energy. Moving particles against their concentration gradient (low to high) requires energy. E(cid:454). (cid:449)e do(cid:374)"t (cid:374)eed e(cid:374)erg(cid:455) to (cid:373)ake a (cid:271)oulder (cid:373)o(cid:448)e do(cid:449)(cid:374)hill, (cid:271)ut (cid:449)e do (cid:374)eed. But the plasma membrane surrounding the cell is impermeable to ions: energy to move it uphill.
