HHP 3500 Lecture Notes - Lecture 9: Peripheral Nervous System, Axon Hillock, Neuroglia

• School: University of Iowa
• Department: Health and Human Physiology
• Course: HHP 3500
• Professor: Peterson Clayton

Document Summary

One way for body to communicate: 1. Nervous system: 2 divisions: central nervous system. Brain and spinal cord: peripheral nervous system. Responsible for connecting sensory system to central nervous system, and connecting central nervous system to effectors. Cell body (soma)- contains the nucleus, organelles. Dendrites-long extensions from the soma, they receive all the signals; branching serves to increase surface area to receive signals. Axon-signal long extension from soma, and carries message to another neuron through branching or an effector in the form of an action potential. Initial segment on axon is called axon hillock, where the message originates. Axon branches to create axon collateral, and then the splitting of those (the final tip) is axon terminal, or varicosities. This is an insulation to prevent ion leakage and increase conduction velocity. The myelination are modified plasma membrane: types of neuron tissue: coating by glial cells. Has one axon, with peripheral and central processes. Efferent neurons- carry commands away from cns.