CNS Histo

Question 1

What is the function of glial cells?

Answer 1

Support cells involved in conduction speed, repair, NT maintenance

Question 2

What is neuropil?

Answer 2

The surrounding meshwork and structure that support the neuronal cell bodies

Question 3

What substance causes neurons to appear opaque in a histological staining? What does it represent?

Answer 3

Nissl substance/bodies

Represents large, basophilic masses of free polysomes and RER

Question 4

What structures on the dendrites are known for their plasticity and ability to increase receptive area of the neurons?

Answer 4

Dendritic spines

Question 5

What are telodendria?

Answer 5

Dilation of branch ends of axons that contact postsynaptic cells

Question 6

What type of neuron is most common throughout the CNS? What do they function as?

Answer 6

Multipolar

Motor neurons, CNS interneurons

Question 7

What is the most common function of bipolar neurons?

Answer 7

Sensory neurons of retina, olfactory mucosa, and inner ear

Question 8

What type of neuron is found in dorsal root and cranial ganglia?

Answer 8

Unipolar/Pseudounipolar

Question 9

What motor protein is utilized in anterograde transport?

Answer 9

Kinesin (uses ATP)

Question 10

What motor protein is utilized by retrograde transport?

Answer 10

Dynein

Question 11

What is the speed of slow transport? What type of transport is this utilized by?

Answer 11

0.2-4 mm/day

Anterograde

Question 12

What is the speed of fast transport? What is conveyed in either direction?

Answer 12

20-400 mm/day

Anterograde: Membrane-limited organelles, sER components, synaptic vesicles, mitos

Retrograde: membrane-limited organelles, molecules endocytosed at axon terminal (toxins and viruses)

Question 13

Most synapses in the body are ___ synapses.

Answer 13

Chemical

Question 14

In an electrical synapse, what generates the potential difference that allows flow of electrical current from one neuron to another?

Answer 14

Presynaptic action potential

Question 15

On a histological image, what would differentiate between a chemical and electrical synapse?

Answer 15

Chemical synapse has a vesicular presynaptic cell

Electrical synapse has visible connexon ptns

Question 16

What protein reinforces the proximal regions of astrocytes?

Answer 16

Glial Fibrillary Acid Protein (GFAP)

Question 17

Astrocytes produce perivascular feet that perform what function?

Answer 17

Modulate blood flow and move nutrients and metabolites between neurons and capillaries

Question 18

What is the function of perineural feet?

Answer 18

Modulate electrical impulses from the neurons

Question 19

What is the embryological origin on Schwann cells?

Answer 19

NCC

Question 20

What are glial cells derived from?

Answer 20

Neuroepithelium

Question 21

What type of epithelium are ependymal cells?

Answer 21

Columnar or cuboidal cells

Question 22

Where are ependymal cells located?

Answer 22

Lining the ventricles of the brain and central canal of the spinal cord

Question 23

Where is choroid plexus found?

Answer 23

Roofs of 3rd and 4th ventricles

Parts of lateral ventricular walls

Question 24

What is the choroid plexus composed of?

Answer 24

Thin layer of well-vascularized pia mater covered by cuboidal ependymal cells

Question 25

What neural cells act similar to phagocytes and are the major mechanism of immune defense in the CNS?

Answer 25

Microglia

Question 26

What are the 3 layers of cerebral cortex?

Answer 26

1. Molecular layer 2. Purkinje cells 3. Granular layer

Question 27

What are the cerebral cortical layers?

Answer 27

1. Plexiform layer 2. Small pyramidal/External granular layer 3. Layer of medium pyramidal cells (External pyramidal layer) 4. Granular layer 5. Large pyramidal cell layer 6. Polymorphic layer

Question 28

What cortical layers contain the most pyramidal cells?

Answer 28

3 - Layer of medium pyramidal cells 5 - Large pyramidal cell layer

Question 29

What tissue is this? What is the outer layer? What is the deep layer?

Answer 29

Question 30

What cerebral structures are considered archicortex?

Answer 30

Hippocampus Dentate gyrus

Question 31

What comprises the polymorphic layer of archicortex?

Answer 31

Nerve fibers Cell bodies of interneurons

Question 32

What comprises the molecular layer of archicortex?

Answer 32

Hippocampus: Dendrites of pyramidal cells Dentate gyrus: Dendrites of granule cells

Question 33

The limbic hilus is the region where what structures meet?

Answer 33

Hippocampus Dentate gyrus

Question 34

A pt's MRI shows thinning of cerebral gyri in the frontal and temporal lobes. What disease process is associated with this finding?

Answer 34

Alzheimer's disease

Question 35

What structures are found in a histological slide for a patient with this disease?

Answer 35

Amyloid B plaques Neurofibrillary tangles