Medsci L2. Spinal cord Flashcards
Number of cervical nerves
8
Number of thoracic nerves
12
number of lumbar nerves
5
How many pairs of nerves are in the spinal cord in total?
31
where is the best place for injections in the back?
Below the spinal cord to avoid damaging the spinal cord.
Pia Mater
The pia mater is the innermost layer of the meninges. The pial cellular layer firmly adheres to the surface of the spinal cord
Dura Mater
Dura mater is a thick membrane made of dense irregular connective tissue that surrounds the brain and spinal cord. It is the outermost of the three layers of membrane called the meninges that protect the central nervous system.
What are the 3 meningeal layers?
dura mater, arachnoid mater and pia mater
Cauda Equina
The collection of nerves at the end of the spinal cord.
Discriminative sensation information
Ability to tell 2 different points of touch apart
Meissner’s corpuscle
consist of a cutaneous nerve ending responsible for transmitting the sensations of fine, discriminative touch and vibration
Pacinian corpuscle
Pacinian corpuscles detect gross pressure changes and vibrations
What type of neuron is myelinated in the spinal cord?
Pseudounipolar neurons
What type of neurons are responsible for pain/temperature?
Unmyelinated neurons with free nerve endings( non-encapsulated)
-End at the back of the grey matter
what is the speed of signal in pseudounipolar sensory neurons?
50 m/s
What is the speed in unmyelinated pain/temp neurons?
1 m/s
dorsal root ganglion
bundle of cells bodies in dorsal root
how does the sensory pseudounipolar neuron split?
one end goes to grey matter(sinapses with other neurons) and the other to white matter(straight to the brain)
What is convergence and what is its function?
1 sensory neuron picks up information from other neurons and then carries it to the brain. This is done to reduce the volume of the spinal cord as there are less neurons going up to the brain.
Where is motor and sensory information carried?
motor carried forward through ventral root
sensory carried towards the back through the dorsal root
where is white and grey matter located in the spinal cord?
white on the outside, grey on the inside.
cervical enlargement
area where the information goes to and from the arms
lumbar enlargement
area of the spine where the information goes to and from the legs
3 protective layers of the spinal cord
pia mater
arachnoid mater
dura mater
where are opioid receptors located?
dorsal gray root
where are cell bodies for upper motor neurons located?
precentral gyri of the cerebral cortex
where are cell bodies of lower motor neurons located?
anterior gray horns of the spinal cord
