Exam 2 - Nervous System A&P Flashcards
what does the CNS consist of
brain and spinal cord
what does the PNS consist of
cranial/spinal nerves and the autonomic nervous system
what do the ascending tracts of the CNS do
carry sensory information from the periphery, muscles, and organs to the higher levels of the CNS
what do the descending tracts of the CNS do
carry impulses from the brain and result in voluntary muscle movement
what does the neuron consist of
cell body, axon, and several dendrites
what is the cell body
the metabolic center of the neuron
what are dendrites
short extensions from the body that receive and conduct nerve impulses
what are axons
extend varying distances from the cell body and carry nerve impulses
- can be myelinated or unmyelinated
what is the myelin sheath
white lipid substance that insulates and helps conduct the impulses
what are types of neuroglia
- oligodendrocytes
- schwann cells
- astrocytes
what are oligodendrocytes
produce the myelin sheath for nerve fibers in the CNS and help make up the “white matter” of the brain
what are schwann cells
myelinate the nerve fibers in the periphery
