PSL350H1 Lecture Notes - Lecture 5: Rho Family Of Gtpases, Semaphorin, Growth Cone
Document Summary
In the brain, you have billions of cells. And you only want to target one. During development, the cells are dividing. In the cns, during development, cells divide. The will stop dividing then initiate differentiation. Some of these cells will be come neuronal cells: these neuronal cells extend a few processes. Many dendrites, just after differentiation has been initiated: one of the dendrites will be longer than the others. That becomes the axon: the axon then connects with the target cell. There are many dendrites, one axon (most of the case, but there are some neurons with 2 axons. ) Growth cone - eye of the axons. Image: staining of a growth cone. It is represented like a hand, there are fingers It is sensing the environment. Have positive and negative regulatory proteins to tell which is the right direction. Chemorepulsive - repulse over long distances to make sure the axons never enter specific tissues.
