Flashcards in 021914 1 Neurocytology and CSF SDL Deck (35):
What are lipofuscin granules?
residual, undigested, lysosomal material
accumulates with age
What is melanin?
by-product of catecholamine (non-peptide neurotransmitters) synthesis
Unmyelinated neurons are involved in sensing:
pain and temperature
Myelinated neurons are involved in sensing:
touch, vibration, joint position
This process has increased myelination, is arborized, and lacks golgi complex. Dendrite or axon?
This process contains nissl bodies, free ribosomes, has more microtubulues than neurfilaments, and cannot leave the CNS to enter periphery. Dendrite or axon?
Do axons have free ribosomes?
Axon hillock contains free ribosomes, but lacks nissl substance and polyribosomes. T or F?
Axons contain more neurofilaments than microtubules T or F?
What do astrocytes do? (4)
maintain blood brain barrier
insulate/cover soma and dendrites without synapses
maintain ionic environment of and determine sites of nodes of ranvier.
What are the two types of astrocytes?
fibrous astrocyte, protoplasmic astrocyte
What is the difference between fibrous and protoplasmic astrocytes?
fibrous contains lots of GFAP and are found in grey and white matter, protoplasmic do not contain GFAP and are only found in grey matter.
What do oligodendrocytes do? (2)
myelinate CNS axons
assist astrocytes in covering unmyelinated soma
What do microglia do? (1)
participate in inflammatory/phagocytic activities during injury
What types of cells line the interior of the CNS (ventricles of brain, spinal cord), may be able to divide, and participate in passage of substances between CNS and CSF.
What type of cells constitute the covering of the choroid plexus, begin as ependymal cells but differentiate after contacting the pia mater, and create occluding junctions present at the apical surfaces of cells--forming the blood-CSF barrier?
choroidal epithelial cells
Where is grey matter located?
spinal cord (inner)
cerebrum and cerebellum surface
brainstem surface and depths
Where is white matter located?
spinal cord (outer)
cerebrum and cerebellum depths
brainstem surface and depths
Contains neuropil, astrocytes, oligodendrocytes, lots of microglia, and is very richly vascularized. Grey or white matter?
Is organized by nuclei (clusters of neuronal cell bodies) and laminar (layers of neuronal sonata). Grey or white matter?
Grey or white matter consists mainly of myelinated axons?
Do grey and white matter contain oligodendrocytes, astrocytes, and microglia?
Is white matter richly vascularized?
no, axons don't require as much blood as cell bodies.
Does white matter contain soma?
What is the difference between chemical and electrical synapses?
chemical involve neurotransmitters, electrical involve gap junctions which form passages for small ions/molecules, allowing nuclei to simultaneously fire.
What is the terminal end of a neuromuscular synapse called?
motor end plate
What type of a synapse is a neuromuscular synapse? chemical or electrical?
chemical, releases neurotransmitters
What are secretomotor synapses?
What are neurosecretory synapses?
reach from hypothalamus to hypophysis to release vesicles containing vasopressin, oxytocin, etc.
_______ is an ultrafiltrate of plasma consisting of electrolytes and proteins, produced by selective filtration through choroid epithelium.
CSF circulates throughout the ventricular system and subarachnoid spaces and is reabsorbed by _________ back into venous system.
arachnoid granulations (one way valves)
______ is formed by tight junctions of capillary cells lacking fenestrate, not astrocytes.
blood brain barrier
What is the difference between a communicating and non-communciating hydrocephalus?
communicating: CSF flow between ventricles occurs. non-communicating: CSF flow between ventricles does not occur.
Congenital or acquired abnormalities in circulation caused by stenosis of aqueducts (which connect ventricles) prevent CSF from flowing between ventricles is example of what type of hydrocephalus?