2.3 Cranial Nerves Flashcards
What are the two subdivisions of the peripheral nervous system?
somatic
autonomic
What does the somatic nervous system contain?
nerves that control skeletal muscles, skin and joints
What are receptors?
exterior sense organs that receive environmental stimuli and initaite nerve impulses towards the CNS
What are effectors?
muscle fibers and glands that bring about a reaction to the stimulus in the PNS
What does the autonomic nervous system contain?
nerves that control smooth muscles of the internal organs and glands
What are visceral motors neurons?
nerves in the autonomic nervous system
When are nerves in the autonomic nervous system known as viseral motors?
when they control smooth muscles or involuntary functions
How many pairs of cranial nerves do humans have?
twelve
What are the types of cranial nerves?
sensory nerves
motor nerves
mixed nerves
What are sensory cranial nerves?
long dendrites of sensory neurons only
What are motor cranial nerves?
long axons of motor neurons only
What are mixed cranial nerves?
have both long dendrites and long axons
What do all cranial nerves (except one) innervate?
head
neck
face
What is the one cranial nerve that does not innervate the head neck or face?
vagus nerve
What does the vagus cranial nerve innervate?
internal organs
What do special sensory cranial nerves do?
carry information responsible for sight, smell, hearing, and balance
What is CN 1?
olfactory nerve
What type of cranial nerve is the olfactory nerve?
special sensory nerve
What is the function of CN1?
sense of smell
Where does CN1 originate and terminate?
originates = olfactory epithelium
terminates = olfactory bulbs
