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Flashcards in Nerves Deck (50)
1

Where are ganglion located?

Outside CNS

2

What does the central nervous system consist of?

Brain and Spinal cord

3

What does the peripheral nervous system consist of?

Everything except brain and spinal cord

4

What is the cell body called?

Soma, perikaryon

5

What is Nissl substance and where is it located?

Clumps of rER located in the cell body and dendrites

6

Does the soma have a nucleolus?

Yes

7

What is the background of nervous tissue called?

Neutropil

8

Do dendrites conduct signals toward or away from the soma?

Toward

9

D axons conduct signals towards or away from soma?

Away

10

When do axons not transmit information away from the soma?

Pseudounipolar neurons

11

What cells produce myelin in the central nervous system? Peripheral?

Central: oligodendrocytes
Peripheral: Schwann cells

12

What are the 3 types of neuron shape?

Bipolar, pseudounipolar, multipolar

13

What are bipolar neurons used for?

Sight, hearing, smell

14

What are pseduounipolar nerves used for?

Regular sensory neurons

15

What are multipolar neurons used for?

Most motor neurons

16

Where can synapses occur?

Cell body, axons, dendrites

17

What is bodain classification of neurons?

Dendritic zone (area that is stimulated/inhibited)

Axonic zone (conducting part)

Telodendritic zone (terminal mods that allow for transfer of information at synapse)

18

What is the bodain classification of a bipolar neuron?

Dendritic zone: Dendrites

Axonic zone: Axon & cell body

Telodendritic zone: End of axon

19

What is the bodain classification of a pseduounipolar neuron?

Dendritic zone: on lower part of neuron

Axonic zone: Axon, cell body

Telodendritic zone: right above cell body

20

What is the bodain classification of a multipolar neuron?

Dendritic zone: Dendrites & cell body

Axonic zone: Axon

Telodedritic zone: End of axon

21

What are the neuroglial cells of the central nervous system?

Astrocytes, Microglia, Oligodendrocytes, Ependymal cells

22

What are the glial cells of the peripheral nervous system?

Satellite cells (ganglionic gliocytes)

Schwann cells (neurolemmocytes)

23

What is the purpose of neuroglial cells?

To provide support to the central nervous system because there is little CT

Form scars by proliferating astrocytes after injury

Nutrition, communication

24

What is an astrocyte?

Largest neuroglial cell

Protoplasmic is found in grey matter

Fibrous is found in white matter (surround nodes of ranvier)

25

What is the purpose of astrocytes?

Recycle neurotransmitters, maintenance of synapses, maintain the blood-brain barrier, antigen-presenting

26

What diseases are astrocytes key in?

Alzheimers, ALS, Alexander's disease

27

Where are oligodendroglia located?

In the CNS

In grey matter near perkarya to produce myelin

In white matter to produce myelin

28

How many neurons can one oligodendrocyte envelop?

Several

29

What are ependymal cells?

Line cavity of brain and spinal cord

Contribute to formation of Cerebrospinal fluid

Stem cell properties (proliferate in response to injury, generate neuroblasts and astrocytes)

30

What are microglial cells?

Small and dense phagocytic cells

31

What is the bouton?

Expanded area of the axon that contributes the presynaptic membrane

32

Describe the synaptic cleft

Gap between neurons that contains fine filaments and electron dense material

33

What is the subsynaptic web?

Filamentous materials associated with the post synaptic membrane

34

What is the tripartite synapse?

Astrocytic processes at the synaptic cleft form connections with neuronal synapses and each other with gap junctions

35

Does neurogenesis occur?

Yes, throughout life.

Neural stem cells have astrocytic and neuroepithelial potential

Ependymal cells of the central canal are pluripotential

36

What is dedifferentiation?

Progenitor cells are mono or uni-potent. If a cell becomes bipotent it has dedifferentiated to a stem cell

37

What is transdifferentiation?

A cell becoming a cell type from a different embryonic lineage

38

Where is epineurium located?

Around entire nerve fiber

39

Where is perineurium located?

Around each fasicle

40

What are the perineural cells?

A sleeve-like layer of epithelioid cells immediately around fasicles

41

What is endoneurium?

Surrounds individual axons (along with myelin)

42

How many neurons can schwann cells envelop?

One, many schwann cells on one axon

43

Describe unmyelinated fibers

Several nerve fibers sit in simple clefts of schwann cells

44

What is the gap between schwann cells called?

Node of ranvier

45

What is each separate myelin segment referred to as?

Internode

46

Why don't myelin sheaths stain?

They're made of mostly lipids

47

Where are satellite cells located?

Surrounding the perikarya in the ganglion

48

What neuron types do not leave the CNS?

Interneuron, upper motor neuron

49

What are the 3 layers of connective tissue that surround the CNS?

dura mater (outer)
arachnoid (inner)
pia mater (inner)

50

What space is filled with CSF?

Subarachnoid space