Glial Cells

Question 1

What are four main functions of glial cells?

Answer 1

• surround neurones and provide support
• supply them with nutrients
• insulate neuron and facilitate synaptic transmission
• destroy and remove unwanted debris

Question 2

What is the O2A progenitor?

Answer 2

The progenitor to astrocytes and oligodendrocytes.

Question 3

How does differentiation of oligodendrocytes work?

Answer 3

Start as oligodendrocyte precursors (NG2) then they become immature oligodendrocytes (O4) then mature oligodendrocytes.

Question 4

What are schwann cells?

Answer 4

Myelinating cells of the PNS

Question 5

What cells give rise to Schwann cells?

Answer 5

Neural crest cells give rise to schwann cell precursors.

Question 6

How do you get astrocytes?

Answer 6

Neural stem cells undergo specification to an astrocyte precursor which undergoes differentiation to become an astrocyte.

Question 7

What tiles the parechyma?

Answer 7

Microglia

Question 8

What happens when the brains homeostasis is disrupted?

Answer 8

Microglia equipped with a repertoire of immune sensors and reactants allowing rapid reaction to any disruption

Question 9

What is the microglial progenitor?

Answer 9

Erythromyeloid progenitor

Question 10

What are microglia for first 2 weeks of a human life?

Answer 10

Known as Ameoboid cells- they gradually acquire a ramified state and shape of microglia

Question 11

What are astrocyte functions?

Answer 11

• neurogenesis and gliogenesis
• neuronal guidance in brain development

-regulates synaptogenesis and synaptic maturation

Question 12

how many axon-dendritic synapses are surrounded by astrological membranes?

Answer 12

60%

Question 13

How many perforated synapses are surrounded by astrocytes?

Answer 13

~80%

Question 14

Are astrocytes excitable cells?

Answer 14

Yes, in response to stimulation their endoplasmic recticulum release calcium stores.

Question 15

How do astrocytes regulate neuron excitability?

Answer 15

Through gliotransmitters

Question 16

What effects do astrocytes have on glutaminergic signaling?

Answer 16

astrocytes participate on glutamate clearance and provision.

Question 17

Name a gliotransmitter….

Answer 17

ATP

Question 18

How does ATP effect the synapse?

Answer 18

Through paracrine activity through calcium waves in astrocytes and suspresses synaptic transmission

Question 19

Where is the Blood brain barrier?

Answer 19

Between intracerebral blood vessels and brain parenchyma

Question 20

How is the BBB formed?

Answer 20

It’s formed by tight junctions between epithelial cells and astroglial feet

Question 21

Where is the BBB not present?

Answer 21

Circumventricular organs

Question 22

What are microglia?

Answer 22

Macrophages of the brain.

Question 23

What is the brain stem?

Answer 23

A conduit for ascending and descending impulses. Also house very important reflex centres for heart rate blood pressure and respiration

Question 24

What are spinal nerves a mix of?

Answer 24

Motor neurones sensory neurones and sympathetic neurones

Question 25

How many cranial nerves are there?

Answer 25

12 cranial nerves

Question 26

What is cranial nerve 1?

Answer 26

Olfactory nerve

Question 27

What is cranial nerve 2?

Answer 27

Optic nerve