PSY290H5 Lecture Notes - Lecture 4: Myelin, Group C Nerve Fiber, Viscosity
Document Summary
Notes: neural communication - transmission within a neuron. Myelinated say ow" when we pinch it. 100 ms (0. 1 s) to conduct information along 1m. Process of propagation down the length of axons. The neighboring na+ channels have to keep on opening to maintain the signal along the axon. The ap only occurs at the nodes of ranvier. What determines the speed of an ap. Cannot keep the outside and inside separated effectively. Axon needs voltage gated channe;s all along. Attractiveness of ions from inside and outside. Solved problem of axons being too thin. More space for the ions to move around. Alleviates problems associated with stickiness and axoplasmic resistance. Glial cells is to prevent and present a barrier that blocks the passage of +ve and. The sheet covers the semi-permeable leaky membrane. Presents a separation between the inside and the outside of the axon. Greater separation between the +ve and -ve ions.
