Spinal Cord & CNS Protection

Question 1

4 parts of the spinal cord?

Answer 1

1. cerivical
2. thoracic
3. lumbar
4. sacral
5. coccygeal

Question 2

how does reflex arc work?

Answer 2

1. incoming signals synapse at poseterior horn

2. interneurons in intermediate gray signal to efferent motor nerves in anterior horn-> stimulates movement

Question 3

5 steps of conscious thought?

Answer 3

1. pain receptor activation
2. action potential travels through dorsal root ganglion nerve
3. received at posterior horn
4. goes to brain via afferent nerves
5. efferent nerves relay signal to posterior horn

Question 4

3 parts of the grey matter in spinal cord?

Answer 4

posterior/dorsal horn, intermediate gray, anterior horn

Question 5

type of IG neurons in thoracic and upper lumbar?

Answer 5

sympathetic motor neurons (fight-flight)

Question 6

types of IG neurons in sacral level?

Answer 6

parasympathetic motor neurons (rest-and-digest)

Question 7

3 major pathways in white matter of spinal cord?

Answer 7

posterior columns, spinothalamic tract, lateral corticospinal tract

Question 8

function of posterior columns?

Answer 8

senses touch, position

Question 9

function of spinothalamic tract?

Answer 9

senses pain, temperature

Question 10

function of lateral corticospinal tract?

Answer 10

commands voluntary movements

Question 11

3 things that protect CNS?

Answer 11

vertebrae, skull, meninges

Question 12

3 layers of meninges?

Answer 12

1. dura
2. arachnoid
3. pia matter

Question 13

function of dura?

Answer 13

provides mechanical strength

Question 14

function of arachnoid?

Answer 14

acts like valves to control skull pressure

Question 15

function of cerobrospinal fluid?

Answer 15

provides nutrients from blood filtration

Question 16

where do nutrients enter bloodstream from CSF?

Answer 16

via arachnoid villi

Question 17

what 2 things help stabalize head during movement?

Answer 17

CSF, arachnoid trabuculae

Question 18

what occurs when skull pressure is too high?

Answer 18

arachnoid villi open to let CSF out

Question 19

what occurs when skull pressure is too low?

Answer 19

arachnoid villi close so CSF stays in

Question 20

function of blood brain barrier (BBB)?

Answer 20

selectively filter useful things, keep toxins out

Question 21

4 layers of BBB?

Answer 21

1. endothelial
2. pericyte
3. basement membrane
4. glial barrier

Question 22

function of endothelial layer?

Answer 22

regulates transport through BBB

Question 23

function of pericyte layer?

Answer 23

stabilization, regulation of permeability

Question 24

function of glial barrier?

Answer 24

astrocyte endfeet interact w/ blood vessels, regulates dilation to control blood flow

Question 25

3 types of glial cells?

Answer 25

astrocyte, oligodendrocytes, microglia

Question 26

function of astrocytes?

Answer 26

provide nutrients to nerve cells, protect neurons by controlling fluid composition around them

Question 27

function of oligodendrocytes?

Answer 27

make myelin (myelin sheaths) to inc. speed of signal

Question 28

function of microglia?

Answer 28

brain macrophages that remove debris, protects from infection

Question 29

2 parts of BBB that help regulate tight junctions?

Answer 29

pericyte and glial barrier