Monday, 3-21-CNS Histology (Olinger)

Question 1

Where would you tend to find a bipolar neuron?

Answer 1

Sensory structures:
Retina
Olfactory epithelium
Vestibular and auditory systems

Question 2

A ___ neuron is described as a single axon dividing a short distance from the cell body. The short axon of this type of neuron divides into 2 branches: The peripheral branch that carries info from the periphery and the Central branch ending in the SC

Answer 2

Pseudounipolar

Question 3

Where do you find pseudounipolar neurons?

Answer 3

Sensory ganglia of cranial and spinal nerves

Question 4

List 2 examples of a multipolar neurons:

Answer 4

Pyramidal cells and Purkinje cells

Question 5

This multipolar neuron cell type is found in the cerebral cortex: ___

This multipolar neuron cell type is found in the cerebellar cortex and tends to have a HUGE dendritic tree: ___

Answer 5

Pyramidal cell

Purkinje cell

Question 6

List the cerebral cortex layers beginning with the superficial most layer and ending with the deep layer

Answer 6

Molecular layer –> External granular layer –> external pyramidal cell layer –> Internal granular layer –> Internal pyramidal cell layer –> Multiform cell layer –> White matter

Question 7

What are the components of the gray matter in terms of the cerebral cortex layers?

Answer 7

Molecular layer –> External granular layer –> External pyramidal cell layer –> Internal granular layer –> Internal pyramidal cell layer –> Multiform cell layer

Question 8

List the organization of the cerebellum beginning with the outer-most layer:

Answer 8

Molecular layer –> Purkinje cell layer (dendrites then cell bodies) –> Granular (granule cell) layer –> white matter

Question 9

In a histological stain of a synapse, synaptic vesicles would be found in which cell?

Answer 9

The pre-synaptic

Question 10

___ synapse: An axon terminal ending on the soma of a neuron

___ synapse: An axon terminal contacting another axon terminal

___ synapse: An axon ending on a dendrite

___ synapse: An axon terminal facing a dendritic spine

Answer 10

Axosomatic

Axoaxonic

Axodendritic

Axospinous

Question 11

A ___ consists of an expanded head connected to the dendrite shaft by a neck.

Answer 11

Dendritic spine

Question 12

In contrast to the dendritic shaft that contains microtubules, the dendritic spine cytoskeleton consists of ___ associated with the postsynaptic density which is where neurotransmitter receptors and ion channels are localized

Answer 12

Actin filaments

Question 13

___ are present in the CNS and make up the blood-brain-barrier (BBB)

Answer 13

Astrocytes

Question 14

Astrocytes are branching cells of the CNS with cytoplasmic processes ending in expansions called ___

Answer 14

End-feet

Question 15

___ cover neurons (dendrites and cell bodies), the inner surface of the pia mater, and every blood vessel in the CNS

Answer 15

End-feet

Question 16

What are the components of the BBB?

Answer 16

• Tight junctions between endothelial cells are the main components of the BBB
• Basal lamina of the endothelial capillaries
• Perivascular astrocyte end-feet

Question 17

In the CNS, ____ form myelin sheaths around the axons

Answer 17

Oligodendrocytes (derived from glioblasts)

Question 18

Which cell type is responsible for myelination in the CNS?

Answer 18

Oligodendrocytes

Question 19

__ are the phagocytic cells of the CNS

Answer 19

Microglial cells

Question 20

The brain ventricles and the central canal of the SC are lined by a simple cuboidal epithelium known as ___

Answer 20

Ependyma

Question 21

The ependyma consists of these 2 cell types:

Answer 21

• Ependymal cells

- Tanycytes

Question 22

This cell type of the ependyma has cilia and microvilli on the apical domain and abundant mitochondria. The basal domain is in contact with astrocytic processes. Theses cells are attached to each other by belt desmosomes

Answer 22

Ependymal cells

Question 23

These cells of the ependyma are in the 3rd ventricle and specialized with 2 different observable features: 1) basal processes that extend through the astrocytic processes layer to form end-feet on a blood vessel and 2) it’s own cell type that are attached to each other and to ependymal cells by tight junctions

Answer 23

Tanycytes

Question 24

The ___ of the brainstem is lined primarily by ependymal cells (no tanycytes)

Answer 24

Central canal

Question 25

The ___ is ependyma wrapped around fenestrated blood vessels

Answer 25

Choroid plexus

Question 26

The ___ membrane prevents the CSF in the subarachnoid space from coming in contact with the fluid of the EC space of the dura mater.

Answer 26

Arachnoid

Question 27

CSF drains around the cerebral hemispheres to the __ placed along the venous sinus

Answer 27

Arachnoid villi

Question 28

The formation of CSF by the choroid plexus involves the passage of an ultrafiltrate of plasma through the fenestrated endothelium of the blood capillary and the surrounding connective tissue. The ___ cells transform this ultrafiltrate into an excretory product: the CSF

Answer 28

Choroidal epithelial

Question 29

List the layers of meninges from outer to inner:

Answer 29

Dura mater –> Arachnoid mater –> subarachnoid space –> pia mater

Question 30

___ is a single layer of flat cells on the brain surface

Answer 30

Pia mater

Question 31

___ reabsorb CSF

Answer 31

Arachnoid granulations and arachnoid villi

Question 32

___ is tough and collagenous and surrounds the brain and SC

Answer 32

Dura mater

Question 33

A __ neuron has a single axon emerging from either side of the cell body.

Answer 33

Bipolar