CNS vs RNS
What does CNS stand for?
Central Nervous System
Which system is the “fight or flight” system?
Sympathetic
What type of matter makes up the outer columns of the spinal cord?
White matter
Sensory information enters through which root?
Dorsal root
Is the knee-jerk reflex voluntary or involuntary?
Involuntary
What two structures make up the CNS?
Brain and Spinal cord
Which CNS contribute to parasympathetic output?
CN III, VII, IX, X
Which horn receives sensory information?
Dorsal horn
Motor information leaves through which root?
Ventral root
In the reflex arc, what does the sensory neuron detect?
Stretch in the muscle (muscle spindle)
What structures make up the PNS?
All nerves outside the brain and spinal cord
Are sympathetic preganglionic neurons short or long?
Short
What spinal regions contain the lateral horn?
T1–L2 (sympathetic)
What does the dorsal ramus innervate?
Back muscles and skin of the back
What is the function of the interneuron in the reflex arc?
Inhibits the antagonist muscle
What is the main functional difference between the CNS and PNS?
CNS integrates/controls information; PNS carries sensory input & motor output.
Why are parasympathetic preganglionic neurons long and postganglionic neurons short?
Because parasympathetic ganglia are near or inside the target
What anchors the spinal cord laterally and prevents side-to-side movement?
Denticulate ligaments
Why do visceral motor pathways require two neurons while somatic motor pathways use only one?
Visceral motor output must synapse in autonomic
Why does the reflex arc not require the brain to produce a response?
The spinal cord integrates the reflex for faster reaction time.