NEUR 2P36 Chapter Notes - Chapter 1: Nernst Equation, Dynamic Equilibrium, Fluid Compartments
Document Summary
Protein channels allow specially charged molecules to pass: The plasma membrane of a neuron is approximately 8 nm thick. The membrane of a neuron maintains an electrical gradient (a difference in electrical charge) between the inside and outside of a cell. Inside is negatively charged relative to the extracellular fluid. Outside is positively charged relative to intracellular fluid. This difference in electrical charge is called polarization. Balancing these molecules across the neuronal membrane produces the potential for action (action potential). Electrical (electrostatic) gradient: difference in the electrical charge across the membrane. Concentration (osmotic) gradient: difference in the number of ions inside and outside the membrane. Results from the process of balancing ionic charges (+ve or ve: same charges repel one another, opposite charges attract. Results from the process of diffusion (i. e. even distribution of ionic concentrations) through a semi-permeable membrane.
