BIOL 129 Lecture Notes - Lecture 2: Ventral Root Of Spinal Nerve, Autonomic Nervous System, Dorsal Root Ganglion
Document Summary
Vertebral column: houses and protects the spinal cord which passes through vertebral foramen and spinal nerves exit through intervertebral foramen. Nerve: a bundle of nerve fibers (cells) wrapped in connective tissue. Individual neurons may be characterized according to function and physiology. Visible nerves may carry many different types of neurons. Inferior spinal nerves drape down to exit the spine (cauda equina) Originate in the spinal cord, exit through intervertebral foramen. Synapse: electrochemical connection between nerve cells or nerve cells and targets. Ganglion: thickened portion of nerve containing cell bodies, may contain synapses. Plexus: any mixture of nerve fibers, can include nerves from many spinal layers. Sensory nerves (afferent): carry information back to cns. Cell bodies lie outside cns in dorsal root ganglion. Motor nerves (efferent): carry impulses to target outside of the cns (organs, glands, and muscles) *spinal nerves carry both motor and sensory fibers. Autonomic nerves: control smooth muscles and glands (involuntary action)
