Nervous System Flashcards
what do nerves do?
allow us to sense out environment - sensory and special senses
allow us to respond appropriately to the environment
reflex functions
what are the two anatomical subdivisions?
central nervous system and peripheral nervous system
what does the central nervous system include?
brain, spinal cord, central controller
what does the peripheral nervous system include?
all the other nerve tissue not within the CNS, spinal nerves, cranial nerves, autonomic nerves, wiring
what is a collection of nerve bodies called in the PNS and CNS?
PNS - ganglion
CNS - nucleus
what does the myelin sheath do?
increase the speed of conduction along the axon of a nerve
what is the function of an axon?
to conduct information away from the cell body
what is the myelin sheath produced by?
PNS = Schwann cells CNS = oligodendrocytes
which direction is the action potential for motor and sensory?
motor (efferent) = towards the body wall, body cavity or organ
sensory (afferent) = towards the brain
what is a single nerve fibre called?
an axon
what the six modalities an axon can conduct?
somatic sensory function somatic motor function special sensory function visceral afferent function sympathetic function parasympathetic function
what are the four lobes of each cerebral hemisphere?
named according to the cranial bone they lie deep to: frontal, parietal, occipital or temporal
what are the two things the cerebral consists of
sulci and gyri
how many cranial nerves are there?
12 pairs
what are the three cranial fossa?
anterior cranial fossa, middle cranial fossa and posterior cranial fossa
when does the spinal cord pass through in the cranium?
foremen magnum
what is the spinal cord protected by?
vertebral canal
what are the four segment of the spinal cord?
cervical, thoracic, lumbar and sacral/coccygeal
what are the two enlargements of the spinal cord?
cervical and lumbosacral
in what way does the spinal cord connect to the spinal nerves?
bilaterally