Neurons and glia

Question 1

A single undifferentiated cell

Answer 1

Neural stem cell

Question 2

What is the process of brain cells?

Answer 2

1) Cells begin as multipotential stem cells
2) They become progenitor cells which are the precursors for ‘blasts’
3) The precursors of blasts develop into specialised neurons and glia

Question 3

Where are adult stem cells located?

Answer 3

In the brains ventricular zone which surrounds the ventricles, and in the spinal cord and retina or the eye!

Question 4

Do blasts differentiate into neurons or glia?

Answer 4

Some develop into neurons while others into glia (neuroblasts and glioblasts)

Question 5

How does a stem cell develop a brain?

Answer 5

It divides itself into 2 stem cells which both divide again. 1 stem cell dies after each divison so the mature brain contains a constant number of dividing stem cells.

Question 6

Do adult stem cells serve as a source of new neurons for certain parts of the adult brain?

Answer 6

Yes! They may play a role in brain repair after injuries such as stroke or trauma

Question 7

Are neurons specialised to function?

Answer 7

Yes

Question 8

What are the names of the 3 types of neurons?

Answer 8

1) Sensory neurons
2) Interneurons
3) Motor neurons

Question 9

Motor neuron

Answer 9

Send signals from the brain and spinal cord to the muscles.

Question 10

Motor neurons in the brainstem

Answer 10

Project to facial muscles

Question 11

Motor neurons in the spinal cord

Answer 11

Project to other muscles of the body

Question 12

What type of neuron are called the ‘final common path’?

Answer 12

Motor neurons, because all behaviour produced by the brain is produced through them

Question 13

What is the function of sensory neurons?

Answer 13

To bring information TO the central nervous system (brain and spinal cord)

Question 14

What is the function of interneurons?

Answer 14

Interneurons within the brain and spinal cord link up sensory and motor activity in the CNS.

Question 15

What is different about interneurons?

Answer 15

They all have many dendrites that branch extensively and also has an axon which can branch aswell

Question 16

Microglial cell

Answer 16

Small, defensive function

Question 17

Schwann cell

Answer 17

Wraps around PERIPHERIAL NERVES to form insulating myelin

Question 18

Astrocyte

Answer 18

Star shaped, nutritive support and function

Question 19

Ependymal cell

Answer 19

Small, secretes CSF

Question 20

Oligodendroglial cell

Answer 20

Asymmetrical, forms insulating myelin around axons in brain and spinal cord

Question 21

Grey matter (communities)

Answer 21

Acquires its colour from neuronal cell bodies that predominate there

Question 22

White matter (roads)

Answer 22

Consists largely of axons that extend from these cell bodies to form connections with neurons in other brain areas. These axons are covered with an insulating layer of glial cells that are composed of lipids (fat).

Question 23

Reticular matter (suburbia)

Answer 23

Contains a MIX of cell bodies and axons.

Question 24

A large collection of axons projecting to OR away from a nucleus or layer in the CNS

Answer 24

Tract

Question 25

What is the function of a tract?

Answer 25

To carry information from one place to another within the CNS e.g. the optic tract carries info from the retina o other visual centres in the brain.

Question 26

Fibre and fibre pathways that enter and leave the CNS

Answer 26

Nerves

Question 27

After nerves have entered the CNS they are called…

Answer 27

Tracts!