Function of the CNS

Question 1

one of the first to document brain dissections

Answer 1

Leonardo da Vinci

Question 2

da Vinci’s theory on brain activity

Answer 2

it occurs in ventricles

Question 3

phrenology

Answer 3

belief that bumps in the skull correspond to particular brain functions

Question 4

how thick is the cerebral cortex

Answer 4

a few millimeters

Question 5

3 broad functions of the cerebral cortex

Answer 5

1. sensory perception
2. motor control
3. cognitive functions

Question 6

2 functions of basal ganglia

Answer 6

1. movement initiation

2. inhibition of antagonist muscles

Question 7

thalamus function

Answer 7

sensory switchboard which relays specific sensory signals to the cortex

Question 8

what is another name for the hypothalamus

Answer 8

head ganglion of the ANS

Question 9

2 functions of hypothalamus

Answer 9

1. homeostasis

2. fight or flight response

Question 10

3 cerebellum functions

Answer 10

1. motor timing, scaling, coordination, learning
2. balance and gait
3. eye movements

Question 11

4 brainstem functions

Answer 11

1. cardiovascular, respiratory, digestive control
2. sleep/wake cycle and arousal
3. balance and posture
4. locomotor initiating center

Question 12

spinal cord function

Answer 12

locomotor pattern generator

Question 13

meninges

Answer 13

3 membranes covering the brain and spinal cord

Question 14

3 meninges

Answer 14

1. dura mater
2. arachnoid
3. pia mater

Question 15

dura mater

Answer 15

tough outer layer

Question 16

arachnoid

Answer 16

spidery intermediary mesh

Question 17

pia mater

Answer 17

delicate inner layer

Question 18

meningitis

Answer 18

infection of the meninges

Question 19

where is cerebrospinal fluid produced

Answer 19

inner walls of brain ventricles

Question 20

how is cerebrospinal fluid absorbed

Answer 20

reabsorbed into venous blood

Question 21

what happens if cerebrospinal fluid reabsorption is blocked

Answer 21

causes hydrocephalus (water on the brain)
- swollen head

Question 22

how is hydrocephalus treated

Answer 22

surgically with drainage tubes

Question 23

2 functions of cerebrospinal fluid

Answer 23

1. bath and support neural tissue

2. maintain electrolyte balance around neurons

Question 24

glia

Answer 24

supportive cells in CNS

Question 25

ratio of glia cells to neurons

Answer 25

~ 1:1

Question 26

4 types of glia cells

Answer 26

1. astrocytes 2. oligodendrocytes 3. ependymal cells 4. microglia

Question 27

astrocytes functions (5)

Answer 27

1. physically support neurons 2. form blood-brain barrier 3. repair by forming scar tissue 4. turnover (recycle) neurotransmitters 5. maintain electrolyte balance

Question 28

what happens when astrocytes repair neuron

Answer 28

they form scar tissue which prevents regeneration

Question 29

how is astrocyte scar tissue dealt with

Answer 29

broken down by enzymes

Question 30

function of oligodendrocytes

Answer 30

form myelin sheaths that electrically insulate axons

Question 31

function of ependymal cells

Answer 31

produce cerebrospinal fluid

Question 32

function of microglia cells

Answer 32

scavengers that ingest bacteria and debris

Question 33

2 types of brain tumors

Answer 33

1. gliomas | 2. meningiomas

Question 34

gliomas

Answer 34

tumor of glia cells

Question 35

meningiomas

Answer 35

tumor of meninges

Question 36

do neuronal tumors exist?

Answer 36

no, because neurons can't divide

Question 37

how do capillaries in the CNS compare to the rest of the body

Answer 37

they are less porous

Question 38

3 functions of blood-brain barrier

Answer 38

1. protects neurons from chemical fluctuations and harmful agents 2. provides oxygen and glucose 3. selectively transport needed molecules to the brain

Question 39

does the brain have glucose stores

Answer 39

no

Question 40

problems with blood-brain barrier

Answer 40

presents a problem for drug delivery like dopamine in Parkinson's patients

Question 41

sensory afferent axons

Answer 41

convey sensory inputs to the CNS

Question 42

motor efferent axons

Answer 42

convey motor commands from the CNS

Question 43

which 2 types of signals does the spinal cord convey

Answer 43

1. sensory receptors to the brain | 2. brain to effectors

Question 44

neuronal circuitry

Answer 44

generates reflexes and simple rhythmical movements

Question 45

how many spinal nerves?

Answer 45

31

Question 46

breakdown of the spinal nerves

Answer 46

``` 8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygeal ```

Question 47

dermatome

Answer 47

specific area of skin innervated by a spinal nerve

Question 48

myotome

Answer 48

specific set of muscles innervated by a spinal nerve

Question 49

shingles

Answer 49

bands of sores and intense pain due to a spinal cord virus

Question 50

how are shingles related to dermatomes

Answer 50

dermatomes are used to identify which part of the spinal cord is infected

Question 51

what happens when the spinal cord is damaged at a given level

Answer 51

sensation and motor control below that level are fucked up

Question 52

what comprises central grey matter in spinal cord tracts

Answer 52

motoneurons, interneurons, dendrites, and axons

Question 53

what is white matter composed of

Answer 53

bundles of axons (tracts)

Question 54

function of white matter

Answer 54

convey sensory signals going to and from the brain

Question 55

where do sensory afferents enter the spinal cord

Answer 55

through dorsal roots

Question 56

what happens after sensory afferents enter the spinal cord

Answer 56

they bifurcate into ascending and descending columns

Question 57

bifurcate

Answer 57

split

Question 58

what do descending branches do

Answer 58

travel caudally 2-3 spinal segments

Question 59

what occurs in the first 2-3 spinal segments

Answer 59

every millimeter, axons send branches into grey matter of the spinal cord

Question 60

where are motoneurons located

Answer 60

the ventral horn