3 Neurons, Glia, CNS Histology Flashcards
What is the “notch” and what does it do?
Transmembrane protein that undergoes cleavage of its intracellular domain where it INHIBITS expression of pro-neural genes.
The cell body contains cellular _______. They have many mitochondria which means ____ energy production.
One axon that arises from a _______ that doesn’t branch proximally
______ which there are usually multiple of, can branch, neurofilaments and microtubules
organelles. HIGH
Hillock
Dendrites
What morphology has multiple dendrites, one axon? Which one has one axon with common stem and then sending two branches? Which one has one dendrite and one axon?
Multipolar
Pseudopolar
Bipolar
What are the 3 primary sensory neuron receptors? What are they responsible for?
What’s the process of converting sensory input into a form interpretable by the nervous system is______?
Mechanoreceptors: audio, vibration, tactile, thermoreceptors, nociceptors..
Chemoreceptors: taste and olfactory
Photoreceptors: rods & cones in retina
Transduction
Motor neuronal axons often end in fine branches known as terminal _____. They form ______ between nerve cells. The site at which an axon terminal communicates with another neuron is called a ______.
Arbors
Synapses
Synapses
Intraneural transport
What are the 5 steps in transmission?
Synthesis Storage Transport Release Reuptake
Axonal transport
Neurotransmitters and other substances are transported along _________ of the axons in both directions.
Anterograde transport (away from the cell) through proteins ________.
Retrograde transport (toward cell body) via _______
Microtubules
Kinesins
Dyneins
Kinesins
Use ___ to “crawl” along the microtubules
Dyneins
Retrograde transport allows neuron to respond to ______ factors. Viruses and toxins
ATP
Growth
The _____ fasciculus and lemniscus are bundles of parallel neurons (axons) in the CNS. Optic tract.
Dorsal root ganglia is in the ___
The term ________ includes cells that are not excitable:
__________-support neurons, isolate CNS from others, scars
_______________- provide myelin sheaths to neurons(axons) within the CNS
_________-immune and inflammatory functions (neural macrophages)
_________ cells-neuro epithelium
Tract
PNS
Neuroglia (glia or ‘glue’)
Astrocytes
Oligodendrocytes
Microclimate
Ependimal cells
What are Astrocytes?
The protoplasmic type are found: in the ____ matter
The fibrous type are found: -in the _____ matter.
Highly branched cells that have a ____-like appearance.
provide structural and functional support to neurons, isolate CNS from other tissues, involved in formation of astrocytic scars
grey
white
star
(LO) Which types of cells give rise to which types cancer or tumors? (2 types of glial tumors, 2 brain tumors)
Ependymoma: a benign tumor
-Derived from ependymal cells.
-Children: arises in the fourth ventrile, adults: arises in cauda equina
-Can produce non-communicating hydrocephalus
Oligodendroglioma: a benign, frontal lobe tumor that frequently calcifies
-Derived from oligodendrocytes
-Primarily occurs in adults
CNS Lymphoma:
-Majority are metastatic high-grade B-cell non-Hodgkin lymphomas.
-Primary CNS lymphomas occur in AIDS
-Present on film with ring-enhancing lesions
Metastases: MOST COMMON BRAIN MALIGNANCY IS METASTASIS
-Lung, breast, melanoma, kidney, prostate cancer.
-Present on film as brighter, less dense
(LO) What types of brain cells can undergo mitosis and proliferate (neurons vs glia)? For each type of primary brain tumor, which brain cell type or tissue is the origin of that tumor type? What kinds of tumors or cancer invade the CNS from elsewhere in the body?
Astrocytes retain the ability to proliferate. They can fill the space in response to injury of the brain, resulting in an astrocytic scar.
Astrocytes are also able to evade the control of cell division (=why the majority of CNS tumors are astrocytic origin)
Microglia, the macrophages of the CNS, also migrate to the site of injury and proliferate. They are the CNS’s immune cells.
(LO) In Multiple Sclerosis, what events lead to entry of immune cells into the brain?
What is the specific form of damage that results? Does MS involve damage to neurons or other cell types of brain cells?
-Some of the Th-1 cells are activated and break through the blood-brain barrier (BBB). These few Th-1 lymphocytes trigger an inflammatory response, which increases the permeability of the BBB.
T-cell-mediated microglial activation and further macrophage recruitment from the blood stream is critical for inflammatory demyelination in MS.
(LO) Describe all the components of the “neurovascular unit” or the blood-brain barrier (BBB), including features of the endothelial cells, astrocytes, and macrophages. What substances or cells are normally blocked from entry into the brain by the BBB? Can blood-borne immune cells cross the blood-brain barrier?
Neurovascular Unit (NVU) Components of the BBB:
- includes brain endothelial cells with their basement membrane
- pericytes, residing on the abluminal surface of capillaries
- astrocytes, which extend cellular processes that almost completely ensheath the blood vessels
- perivascular macrophages
(LO) What are ependymal cells and what do they do?
a type of glial cell that lines the ventricles in the brain and central canal of the spinal cord. These are nervous tissue cell with a ciliated simple columnar form, much like that of some mucosal epithelial cells. The cilia function to beat in a coordinated pattern to influence the direction of flow of CSF. (Also thought their cilia’s movement facilitates the distribution of neurotransmitters.)
