Glia and Neurons

Question 1

What is the “cell theory” and who proposed it?

Answer 1

The tissues of all organisms are composed of cells

Proposed by T. Schwann

Question 2

What is the “neuron doctrine” and who proposed it?

Answer 2

Neurons are special cases of the cell theory

Proposed by Ramon y Cajal

Question 3

Ramon y Cajal used _____ studies and the methods developed by _____ to show that neurons are not continuous.

Answer 3

lesion/degeneration

Golgi

Question 4

Transmission of nerve impulses shows a _____.

Answer 4

delay

Question 5

Flw of information in a neural chain is _____.

Answer 5

unidirectional

Question 6

Transmission at synapses was found to be _____ as well as ______.

Answer 6

excitatory

inhibitory

Question 7

“Glia” comes from the Greek word for _____.

Answer 7

glue

Question 8

Glia cells outnumber neurons by a ration of ~:

Ratios vary considerably by brain area.

Answer 8

3

1

Question 9

_____ surround neurons and hold them in place.

Answer 9

Astrocytes

Question 10

_____ and _____ supply nutrients and oxygen to neurons.

Answer 10

Astrocytes

Ependymal cells

Question 11

_____ insulate one neuron from another.

Answer 11

Oligodendrocytes

Question 12

_____ destroy pathogens and remove dead neurons.

Answer 12

Microglia

Question 13

_____ modulate neurontransmission by making more or less neurotransmitter-precursor available.

Answer 13

Astrocytes

Question 14

Microglia are _____.

Answer 14

phagocytes

Question 15

Microglia arise from _____ of blood cells outside the CNS.

Answer 15

progenitors

Question 16

In microglia’s “resting state,” they _____.

Answer 16

move around and survey their domain for debris.

Question 17

After injury or inflammation, microglia are _____ and migrate to the site of injury to help clear dead and dying cells.

Answer 17

activated

Question 18

Microglia _____ the debris in the brain.

Answer 18

phagocytose

wrap around and “swallow”

Question 19

Microglia can also produce small molecules called _____ that trigger cells of the immune system to respond to the injury site.

Answer 19

cytokines

Question 20

Microglia can become _____, which contributes to neurodegenerative disorders.

Answer 20

overactivated

Question 21

Macroglia consist of _____ and _____.

Answer 21

astrocytes

oligodendrocytes/schwaan cells

Question 22

Astrocytes have numerous projections that anchor neurons to the _____.

Answer 22

blood supply

Question 23

Astrocytes regulate the external chemical environment of neurons by removing _____.

Answer 23

excess ions

particularly potassium

Question 24

Astrocytes form the _____ that protects the brain.

Answer 24

blood-brain barrier

Question 25

Astrocyte activity is linked to _____ in the brain, and this is what is acutally being measured in _____.

Answer 25

blood flow | fMRI

Question 26

Astrocytes are important for neurotransmitter _____ and _____ of the metabolic activities of neurons.

Answer 26

synthesis | regulation

Question 27

Astrocytes take up and recycle _____ and _____ that are released at synaptic clefts.

Answer 27

GABA | glutamate

Question 28

Astrocytes release _____ which can be used by neurons to make new glutamate and/or GABA.

Answer 28

glutamine

Question 29

In the CNS, myelin is made by _____.

Answer 29

oligodendrocytes

Question 30

In the peripheral nerves, myelin is made by _____.

Answer 30

Schwann cells

Question 31

Each Schwann cell makes one segment of _____.

Answer 31

myelin

Question 32

Each oligodendrocyte makes multiple segments of myelin that wrap around _____ axons.

Answer 32

several

Question 33

_____ is an autoimmune disease that often progresses to physical and cognitive disability.

Answer 33

Multiple sclerosis

Question 34

Onset of MS usually occurs in _____.

Answer 34

young adults

Question 35

The name "multiple sclerosis" refers to the scars in the _____.

Answer 35

white matter

Question 36

MS is typically _____ or _____.

Answer 36

``` relapsing remitting (discrete attacks) slowly progressive ```

Question 37

MS destroys _____.

Answer 37

oligodendrocytes

Question 38

MS results in a thinning or complete loss of _____ and, less frequently, the transection of the _____.

Answer 38

myelin | axons

Question 39

Ramon y Cajal used _____ studies and the methods developed by _____ to show that neurons are not continuous.

Answer 39

lesion/degeneration | Golgi

Question 40

_____ modulate neurontransmission by making more or less neurotransmitter-precursor available.

Answer 40

Astrocytes

Question 41

_____ arise from neuroepithelial cells (_____) after the onset of neurogenesis.

Answer 41

Radial glia cells | stem cells of the nervous system

Question 42

In the _____ nervous system, radial glia function both as neuronal progenitors and as a scaffold upon which newborn neurons migrate to _____.

Answer 42

developing | guide the growth of neurons

Question 43

In the _____ brain, the _____ and _____ retain some radial glial cells

Answer 43

mature cerebellum retina

Question 44

Pseudo-unipolar cell contains no _____, but an axon that splits into _____ branches.

Answer 44

dendrites 2 (peripheral nervous system/spinal cord)

Question 45

At rest, the neural membrane is mostly permeable to _____ ions.

Answer 45

potassium (K+)

Question 46

The so-called “resting-membrane potential” is maintained by the _____ pump.

Answer 46

Na+-K+

Question 47

Shifts in neuronal potential either excite the neuron (_____ = excitatory), or inhibit the cell (_____ = inhibitory)

Answer 47

depolarization | hyperpolarization

Question 48

Identity of information (e.g. sensory input) is based on _____.

Answer 48

wiring

Question 49

Intensity of the action potential is based on _____.

Answer 49

frequency