Neurology- Anatomy and Physiology Flashcards
Describe neurons
these are the signal-transmitting cells of the nervous system. They are permanent, and do not divide in adulthood.
What are functional parts of neurons?
dendrites (receive input), cell bodies, and axon (send output)

Cell bodies and dendrities can be seen on what?
Nissle staining (stains RER)
NOTE: RER is not present in the axon so cant be seen this way
What is Wallerian degeneration?
injury to an axon causes degeneration distal to the injury and axonal retraction proximally; allows for potential regeneration of axon (if in PNS)
What is this and what are its roles?

Astrocyte- phsyical support; repair; K+ metabolism; removal of excess neurotransmitters; component of BBB; glycogen fuel reserve buffer
What is the main astrocyte marker?
GFAP
What are microglia?
phagocytic scavenger cells of the CNS activated in response to tissue damage
What is the role of myelin?
it increases the space constant and conduction velocity of signals transmitted down axons, with saltatory conduction of action potentials at the nodes of Ranvier, where there are high conc of Na+ channels
Each Schwann cell myelinates ___ PNS axon
only 1
Schwann cells may be injured in what disease?
Guillain-Barre syndrome
What is acoustic neuroma?
a type of schwannoma, typically located in the internal acoustic meatus (CN VIII).
BILATERAL acoustic neuroma is strongly associated with what?
neurofibromatosis type II
What do olgiodendroglia do?
myelinate axons of neurons in the CNS. Each oligodendrocyte can myelinate many axons (~30). This is the predominant type of glial cell in white matter
Below: “fried egg” appearance

Oligodendrocytes can be injured in what diseases?
MS, progressive multifocal leukoencephalopathy (PML), and leukodystrophies
What are the main types of sensory receptors?
- free nerve endings
- Meissner corpuscles
- Pacinian corpuscles
- Merkel discs
- Ruffini corpuscles
What are the types of free nerve endings?
C-slow, unmyelinated fibers
A(delta)- fast, myelinated
What do free nerve endings sense?
pain and temp
Meisnner and Pacinian corpuscles and Merkel discs are all described as ‘large, myelinated fibers that adapt quickly. Where are Meissner corpuscles found?
glabrous (hairless) skin
Meisnner and Pacinian corpuscles and Merkel discs are all described as ‘large, myelinated fibers that adapt quickly. Where are Pacinian corpuscles found?
deep skin layers, ligaments, and joints
Meisnner and Pacinian corpuscles and Merkel discs are all described as ‘large, myelinated fibers that adapt quickly. Where are Meckel discs found?
fingers tips and superficial skin
What do Meissner corpuscles sense?
dynamic fine/light touch, position sense
What do Pacinian corpuscles sense?
vibration and pressure
What do Meckel discs sense?
pressure, deep static touch (e.g. shapes, edges), position sense
What are Ruffini corpuscles?
dendritic endings with capsules, adapt slowly



