Nervous tissue II Flashcards Preview

Year 1 Cell Biology > Nervous tissue II > Flashcards

Flashcards in Nervous tissue II Deck (19):
1

Gray matter consists of:

Nerve cell bodies and neuroglia

2

White matter consists of:

Myelinated nerve cell axons with some unmyelinated axons and neuroglia

3

What are ganglia?

Collections of nerve cell bodies in the PNS

4

Thoracolumbar outflow corresponds to what spinal levels?

T1 - L2

5

Craniosacral outflow corresponds to what spinal levels?

Cranial nerves + S2 - S4

6

What does the enteric division of the nervous system control?

Peristalsis, gland secretions, blood flow through GI tract

7

What are the classifications of synapses (based on morphology)?

1. Axodendritic2. Axosomatic3. Axoaxonic

8

Where are electrical synapses located in humans?

1. Brain stem2. Retina3. Cerebral cortex

9

Electrical synapses have what kind of intercellular communication?

Gap junction

10

What are the components of a chemical synapse?

1. Presynaptic element2. Synaptic cleft3. Postsynaptic membrane

11

What is kiss-and-run fusion?

When a synaptic vesicle only partially unloads contents

12

What is collapse fusion?

When synaptic vesicle unloads entire contents and fuses to membrane, to be recycled later when membrane gets too large

13

What is choroid plexus located?

Ventricles of brain

14

What are the components of choroid plexus?

1. Folds of pia mater2. Ependymal cells - simple cuboidal epithelium held together by zonulae occludentes

15

Does the brain have lymphatics?

No

16

Where is CSF reabsorbed?

Arachnoid villi in superior sagittal sinus

17

What is Wallerian degeneration?

Segment of PNS axon distal to injury degenerates (anterograde)

18

What is involved in anterograde changes in PNS nerve injury?

1. Segment distal to injury degenerates (Wallerian degeneration)2. Phagocytic cells derived from Schwann cells and blood-derived monocytes clean up debris3. Schwann cells proliferate and along with their external lamina form tubules

19

What is involved in retrograde changes in PNS nerve injury?

1. Proximal to site of injury2. Cell body swells3. Chromatolysis - Nissl bodies move to periphery 4. Nucleus moves to periphery5. Axon grows sprouts and Schwann cells guide them toward target cell6. Essential cells: macrophages, fibroblasts, basal lamina, Schwann cells