Ch 12 Nervous System - Anatomy Flashcards
functions of nervous system
sensory input, integration, motor output
sensory input (an example)
information from the joints being sent to brain about body’s position in space
integration (an example)
brain compares the info from joints to past experience
motor output (an example)
after brain makes it’s calculations, it will send signals to muscles to contract or relax to avoid falling
central nervous system
brain and spinal cord
integration and command center
peripheral nervous system
paired cranial and spinal nerves
carries messages to and from spinal cord and brain
two functional divisions of PNS
sensory (somatic fibers carry impulses from skin skeletal muscle joints to brain, visceral transmits signals from visceral organs to brain)
motor (somatic voluntary movement, autonomic involuntary movement)
parts of a neuron
soma (cell body) - input
dendrite - input
axon - conductivity, action potentials
synapse - transmission secretion
three classifications of neurons
multipolar
bipolar
unipolar
multipolar
most common - interneurons in brain, motor neurons
three or more processes
unipolar
mostly sensory nerves in PNS
single process
bipolar
rare special sensory neurons (eye, ear, olfactory mucosa)
two processes
astrocytes
CNS
most abundant, highly branched
provide scaffolding matrix
microglia
CNS
brain immune cells, monitor health of brain
phagocytose bacteria and virus infected cells
ependymal cells
CNS
ciliated cells lining ventricles of brain and spinal cord
circulate cerebrospinal fluid (CFS)
