1D. Glia or Neuroglia

Question 1

derived from a Greek word meaning “glue”, reflects early investigators’ idea that they served a function like glue, to hold the neurons together

Answer 1

glia

Question 2

TRUE OR FALSE: at one time, neuroscientist believed that glia greatly outnumbered neurons

Answer 2

true

Question 3

ratio of neurons to glia

Answer 3

varies from one brain to another

Question 4

wrap around the dendrites connecting to functionally related axons

Answer 4

astrocytes

Question 5

important for generating rhythms, such as your rhythm of breathing; also dilate the blood vessels to bring more nutrients into the most active brain areas

Answer 5

astrocytes

Question 6

tiny cells that act as part of the immune system, removing viruses and fungi from the brain

Answer 6

microglia

Question 7

they proliferate after brain damage, removing dead or damaged neurons.

Answer 7

microglia

Question 8

loss of microglia will lead to ___

Answer 8

seizures

Question 9

prune ineffective synapses and adjust the effectiveness of others

Answer 9

microglia

Question 10

the mechanism that excludes most chemicals from the vertebrate brain; when the immune system cells find a virus, they kill it and the cell that contains it

Answer 10

blood-brain barrier

Question 11

what happens when a few virus do cross the blood-brain barrier?

Answer 11

• microglia fight viruses in the brain but don’t eliminate them
• viruses can harm the brain by reducing blood flow and triggering an excessive immune response

Question 12

the blood-brain barrier depends on the ___ that form the walls of the capillaries

Answer 12

endothelial cells

Question 13

if the blood-brain barrier is such a good defense, why don’t we have similar walls around all our organs?

Answer 13

the barrier keeps out useful chemicals as well as harmful ones