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Jonathan's Neuroscience > Histology > Flashcards

Flashcards in Histology Deck (25):
1

What are the major cells of CNS

neurons and glia cells

2

What are the five sorts of glia cells in the CNS

astrocytes, oligodendrocytes, ependymal cells, satellite cells

3

What are the immune cells of CNS

microglia

4

What is special about the most superficial 1cm of the brain?

consists of 6 layers of different densities. Layer 1 being the most superficial. This 6-layers arrangement is found in different regions of the brain

5

What is the advantage of using silver stain over H&E stain on neurons

can see processes under silver stain and see different neuronal morphology

6

Where is the CSF formed?

CSF is formed by cuboidal cells of the choroid plexus, which is the vascular structure on the wall of ventricles

7

What is the function ependymal cell?

They line the ventricular system and have finger like projections that help the movement of CSF in central canal

8

Give four distinct qualities of neurons

1) specialised for signalling
2) high level of protein synthesis
3) metabolically limited, rely on blood supply for energy
4) terminally differentiated, apart from a group of adult stem cells

9

What are the characteristics of actin

actin is dynamic and can allow shape change and movement. It forms small spines for signal input and output

10

Intermediate filaments are ________ cytoskeletal structures

permanent

11

What are the characteristics of microtubules?

dynamic, composed of tubulin, important for axonal transport, important in disease

12

What is the name of the 1) input zone 2) cell body 3) output zone of a neuron

dendrite, soma, axon

13

Where are the proteins produced in a neuron

in the nissl bodies of the soma. They are rough ER and free ribosomes

14

What are the passive functions of astrocytes

1) neurotransmitter uptake and degradation
2) K+ uptake as depolarisation releases a lot of K+
3) neuronal energy supply. Take in glucose and convert it to something neurons can use
4) maintenance of BBB
5) injury response and recovery

15

What happens if astrocytes are not there to reuptake the neurotransmitters?

the intensity and duration of action potential increase, which is harmful for the neuron

16

How does astrocyte perform its active function

Astrocytes are excitable (by NT, trauma, spontaneous or inflammatory mediators). Calcium is released, which trigger synaptic vesicle release

17

How does astrocyte use calcium to communicate with other nearby cells?

Calcium release from cell will initiate release of gliotransmitters via mechanisms with calcium dependent vesicular release

18

T/F astrocyte releases calcium to directly cause vasoconstriction of blood vessels

False, calcium triggers the release of gliotransmitter vesicles, and it's the transmitter that causes the vasoconstriction

19

Why is it important that astrocyte has a role in blood vessel tone control

Glial cells can directly regulate vascular tone and respond to the energy requirement for the neurons

20

What is the main difference between oligodendrocytes and Schwann cells

Oligodendrocytes (CNS) wrap around several axons
Schwann cells (PNS) wrap around one axon

21

What are Nodes of Ranvier

small gaps between myelin sheath designed for ion conduction

22

What does microglia resemble

phagocytic macrophages

23

What is the function of microglia in 1) normal state 2) injury

1) send out / retract processes to sample nearby synapses
2) converge processes onto inflamed area, release harmful chemicals to control damage

24

Endoneurium surrounds ___1___ , forming the bundle called ___2___ , which is surrounded by ___3___ . Multiple nerve bundles will form a peripheral nerve, which is surrounded by ___4___

1) individual axon
2) fascicle
3) perineurium
4) epineurium

25

What are the two types of ganglion, and what do they contain?

Sensory, containing cell bodies of sensory neurons
Autonomic, containing cell bodies of post-ganglionic neurons.

There are also satellite cells in ganglia