EXCI 257 Lecture Notes - Lecture 1: Sensory Nerve, Electric Potential, Dorsal Root Ganglion
Document Summary
The brain receives sensation, processes it and responds using the motor system. Comprised of the cell body, dendrites and an axon. The axon is covered by a myelin sheath and passes signals from cell body to cell body. Synapse is a structure that permits a neuron to pass an electric or chemical signal to another neuron. Composed of a lipid bilayer, proteins and carbohydrates. Lipid bilayer of the cell membrane is composed of 2 phospholipid layers. Forms an impermeable barrier to water and water soluble substances: ions, glucose, urea. Forms a permeable barrier to lipid-soluble substances: oxygen, nitrogen, carbon dioxide, alcohol. Cell membrane proteins allow transport of substances across the lipid bilayer. Integral proteins - penetrate through the membrane and act as: channels and pores, substance carriers. Peripheral proteins - attach to one surface of the membrane or integral proteins and act as: enzymes, controllers of transport through channels.