Question Answer
What organs are catergorized in the CNS? Brain and Spinal Cord
The grey matter contains… site of neuron cell bodies & synapses
The white matter contains… nerve tract
What are the parts of the brain? cerebrum, cerebellum, pons& medulla, midbrain, and diencephalon
How many cranial nerves are in the brain? 12
Where does the spinal cord extend through? cranial, thorasic, lumbar, and saccral region
How many spinal nerves are there? 31
What organs in the PNS? spinal, cranial nerves and ganglia
Sensory fibers of the PNS travel in what direction? afferent
Motor fibers of the PNS travel in what direction? efferent
What components are composed of the neuron? cell body, dentrite, and axon
What is the cell body of a neuron called and what is its function? it is called a soma and is responsible for metabolic functions
What are dendrites? receptors of synaptic connections- from hundreds to hundreds of other neurons
What is an axon? transmitting process that may have few to many processes
What causes the transmission to be one way from axon of inpt cell to dentrite of output cell because of the properties of synaptic connection
What do somatosensory receptors respond to? sensory receptors respond to stimuli
what is the pathway of somatosensory receptors? pass through spinal cord nerves or brain nerves
somatosensory axis sensory receptors respond to stimuli
what is the path of somatosensory axis pass signals to spinal cord (spinal nn.) or brain (cranial nn.) where is the sensory info from somatosensory axis
what is the direction of the sensory info in somatosensory nerve tracts in cord are ascending
what is the motor axis skeletal muscle responds to output from a- motor neurons of anterior horn of cord grey matter
where does motor axis signals originate output signals originate from cord, from reticular substance of medulla, pons & midbrain, from basal ganglia, from cerebellum, & from cerebral cortex
what is the direction of the sensory info for motor nerve tracts in cord are descending
what is integrative component involves screening out majority of sensory signals (thalamus)
what plays a major role in integtative components synapses play major role in controlling input signals screening many & amplifying others through mechanisms of facilitation & inhibition
stored sensory inputs (memory) reside mainly in the cerebral cortex also a function of synapses
what repeated sensory inputs may facilitate a certain sequence of synapses to such a level of sensitivity that other signals in the brain my excite the same sequence of synapses, independent of any sensory input