CNS/Sensory Flashcards
What are spinal nerves responsible for?
Somatic sensation:
Touch
Temperature
Pain
What is the afferent system?
Sensory input, cell bodies out of CNS (axons out of CNS)
Efferent
Motor output
Cell bodies in CNS
What are the cranial nerves?
Somatic, visual, olfactory, taste, auditory, vestibular
Where do cranial nerves project to?
Brainstem or other parts of the brain
What is the motor output of the CNS called
Efferent (motor output)
Spinal Nerves functions
Somatic sensation
- touch
- temperature
- pain
What are somatic efferent nerves?
Innervate skeletal muscle, only excitatory, motor neurons
What are autonomic efferent part of nervous system do?
Innervates interneurons, smooth and cardiac muscle, excitatory and inhibitory (enteric nervous system)
What is the white matter in the spinal cord?
Axons running up and down the spinal cord
What is the purpose of the central canal?
Allow CSF to flow
Where are the cell bodies of the efferent neurons found?
In the gray matter
Where are the cell bodies of the neurons whose axons carry afferent signals into spinal cord?
In the dorsal root, more specifically dorsal root ganglion
How many cranial nerves are there?
12
How many cranial nerves enter or leave the brain stem?
10 (pairs, one per side) of 12
What are the only two nerves that do not enter or leave the brain stem called?
Olfactory and optic nerves
Steps of Nervous System development
- Fertilized egg (ovum)
- Ball of cells
- Blastocyst (week 1)
- Blastocyst (week 2)
- Blastocyst (week 3)
- Week 3
Week 1 Blastocyst develops
inner cell mass
Week 3 Blastocyst develops
embryonic disk
neural plate
What are the three layers that make up the embryonic disk, and their location.
Ectoderm (outermost layer)
Mesoderm (middle)
Endoderm (inner)
Neural groove
a shallow median groove of the neural plate between the neural folds of an embryo
What develops in week 4 of the neural tube
vesicles
Neural Crest becomes part of
PNS
Neural tube becomes
CNS and part of PNS