335 4.1 Neuroanatomy Part 4

whitish cordlike structure composed of one or more bundles of fibers, courrsing outside the CNS by which stimuli are transmitted from the CNS to a part of the body or vice versa

• part of the nervous system located outside the bony confines of the skull and vertebral column
• includes 12 pairs of cranial nerves and 31 pairs of spinal nerves

all structures made up of neurons or a nerve cell

• soma
• dendrite
• axon
• synaptic cleft
• myoneural junction

cell body

branches off soma which receives info from other neurons and brings it TOWARD the soma

longest process from the soma which transmits info AWAY from the soma

space between neurons across which a nerve impulse is transmitted by a neurotransmitter

synapse with a motor neuron and a muscle fiber

all information in the cell body is pooled together from dendrites and comes here

fatty covering over axons which helps speed up movement of electrical activity down axon

gaps in the myelin sheath

long, thin projections are the end of an axon

compounds responsible for activation of the next neuron

presynaptic v. postsynaptic

• info comes from the cerebral cortex
• is relayed by neurons referred to as 'somatic motor pathways'
• infor goes out the cerebrum, down the brainstem and/or spinal cord, out to muscles of the body (outside the central nervous system)

motor neurons