Glial cells - Cells and Tissues of the nervous system Part 3

Question 1

What are glial cells?

Answer 1

non-excitable supporting cells

Question 2

What is more abundant: neurones or glial cells?

Answer 2

glial cells

smaller but more abundant

Question 3

What is the most populous glial cells?

Answer 3

astrocytes

Question 4

What do astrocytes do?

Answer 4

maintain the blood-brain barrier

Question 5

What are the 4 types of glial cells in the CNS?

Answer 5

Astrocytes
microglia
ependymal cells
oligodendrocytes

Question 6

What do the end feet of astrocytes surround?

Answer 6

capillaries and synapses

Question 7

What is the main role of microglia?

Answer 7

phagocytosis and scar tissue formation

Question 8

Why does the brain need microglia to carry out phagocytosis?

Answer 8

because of the blood-brain barrier

prevents WBC moving out and needs to be a function of a resident cell of the brain

Question 9

Where do you find the ependymal cells?

Answer 9

line cavities of the brain called ventricles

and central anal of the spinal cord

Question 10

What is the role of oligodendrocytes?

Answer 10

secrete myelin for myelination

Question 11

What are the 2 glial cells of the PNS?

Answer 11

Schwann cells
satellite cell

Question 12

What is the role of Schwann cells?

Answer 12

myelination

Question 13

Where do you find satellite cells?

Answer 13

surround neuronal cell bodies

Question 14

Why are the glial cells important clinically?

Answer 14

tumours of the brain called glioma

common

Question 15

What is the blood brain barrier?

Answer 15

barrier created between blood flowing in the capillaries and brain tissue surrounding the capillaries

Question 16

Why do we need the blood brain barrier?

Answer 16

is a protective mechanism that helps maintain a stable environment for the brain

and prevents harmful amino acid and ions present in the bloodstream and blood cells from entering the brain

Question 17

Answer 17

A = endothelium - tight junction

B = foot process of astrocytes

Question 18

How do ions, WBC and gases move in and out of capillaries?

Answer 18

fenestrations

Question 19

Are capillaries in the brain fenestrated?

Answer 19

no

Question 20

What junctions lie between the capillaries in the brain?

Answer 20

tight junctions

Question 21

What do the papilla cells of the capillaries sit?

Answer 21

basement membrane

thick basal lamina

Question 22

What are the 3 layers forming the blood brain barrier?

Answer 22

1. endothelium - tight junction
2. thick basal lamina
3. foot processes of astrocytes

Question 23

In the brain, what substances can pass through the capillaries?

Answer 23

lipid soluble

Question 24

What are the lipid soluble substances?

Answer 24

O2, H2O

Question 25

How does glucose and amino acids pass through the blood brain barrier?

Answer 25

pump mediated

Question 26

What circumventricular organs in the brain do not have a blood brain barrier?

Answer 26

hypothalamus posterior pituitary

Question 27

Why do the hypothalamus and posterior pituitary not have a BBB?

Answer 27

they are endocrine organs allows it to function properly

Question 28

What is the role of the cerebrum?

Answer 28

seat of consciousness

Question 29

Answer 29

A = cerebrum B = cerebellum C = brainstem D = diencephalon

Question 30

Answer 30

A = midbrain B = pons C = medulla D = spinal cord

Question 31

Answer 31

A = thalamus B = hypothalamus

Question 32

What are the 3 sections of the brain?

Answer 32

midbrain pons medulla

Question 33

Where does the lower end of the medulla sit?

Answer 33

foramen magnum

Question 34

What are the vital centres of the brainstem?

Answer 34

cardiorespiratory, pathway for fibre tracts