HLSC 1200U Lecture Notes - Lecture 19: Voltage-Gated Potassium Channel, Resting Potential, Cell Membrane
Document Summary
F: communication network: rapid regulation and integration of body activities. Characteristics: excitability: initiate starting electrical signals, conductivity: communicate using signals. Nerve impulse: electrical signal which travels along the plasma membrane of the neuron, route: received by the dendrites collected at the axon hillock and transmitted along the axon to another cell, occurs in one direction* Membrane potential maintained by plasma membrane of a neuron at rest. Always slightly negative -70 to -90 mv. Anatomy midterm #2: more cations outside, due to ion transport mechanisms and selectively permeability of membrane. If difference 0 to -70 between two sides = polarized membranes. Roles of ion channels in maintaining in rmp. Main ions for changing mp: na, k, movement of these 2 ions create and maintain nerve impulse. K+ channels (voltage gated: a few are opened and allow k+ to passively diffuse out of cell to make rmp become more negative, rest are closed because needs change of voltage to open them.
