S2 Neuro: Intro To Cns

Front 1

The primary function of the nervous system is survival via homeostasis. How is this achieved (3 things)?

Back 1

1. detects internal & external stimuli from environment
2. integrates info to determine response
3. coordinates cells & tissues to respond

*nervous system divided into CNS & PNS

Front 2

What does the nervous system consist of (at the cellular level)?

Back 2

neurons (excitable cells)

their (neuron's) processes

glia (supporting cells)

Front 3

What two things does a neuron consist of?

Back 3

1. cell body (soma or perikaryon)
2. neurites

Front 4

What are the two types of neurites?

Back 4

dendrites & axons

Front 5

(dendrites/axons) project a short distance from the soma and contain receptors that receive chemical signals from other neurons. They taper distally & branch extensively increasing signal reception.

Back 5

dendrites

Front 6

What are the dendritic branches of a single neuron referred to as?

Back 6

dendritic tree

Front 7

(dendrites/axons) are singular projections that may extend long distances w/i the nervous system.

Back 7

axons

Front 8

The beginning of the axon at the soma is the _________________ followed by the _______________

Back 8

axon hillock ("hill")

initial segment ("peak of hill")

Front 9

The initial segment is uninsulated and rich in what?

Back 9

voltage-gated sodium channels

Front 10

The end of the axon is the ____________, which form ___________ with other neurons or effectors

Back 10

axon terminal (terminal button/Fr. button)

synapses

*terminals contain neurotransmitter vesicles

Front 11

Info transmitted w/i the neuron is a/an (electrical/chemical) signal & info transmitted btwn neurons is a/an (electrical/chemical) signal

Back 11

electrical (w/i)

chemical (btwn)

Front 12

The action potential (wave of depolar.) travels from the ____________ to the _________________

What happens next?

Back 12

from the initial segment to the axon terminal


neurotransmitters released from terminal to act on postsynaptic cell membrane

Front 13

How is a signal transmitted further once the receptors receive neurotransmitters?

Back 13

Receptors generate AP that travel to the postsynaptic neuron cell body

Front 14

T/F
neurons are more numerous than glial cells (neuroglia)

Back 14

FALSE

glial cells are much more numerous 10X! (supporting cells)

Front 15

What are glial cells responsible for?

Back 15

-regulating chemical milieu in EC space
-myelinating neurons
-phagocytosis & repair
-lining fluid filled ventricles (cavities) of brain

Front 16

*Chemicals are released from what part of the neuron, allowing it to communicate with another cell?

Back 16

Button (terminal)

Front 17

*Which of the following CNS structures is not considered part of the brain?
cerebrum
cerebellum
brainstem
spinal cord

Back 17

spinal cord



*CNS = brain + spinal cord

Front 18

What is the primary function of the CNS?

Back 18

processing of sensory info & executor of responses

*more complex processing is done in brain

Front 19

T/F

Brain size correlates w/ intelligence

Back 19

FALSE

correlates directly w/ body size

*2% body weight, 15-17% of cardiac output, 20% oxygen

Front 20

T/F
The orientation of the central axis of the nervous system (neuraxis) changes above the brainstem

Back 20

TRUE

Front 21

Define the following ABOVE the neuraxis
rostral
caudal
ventral
dorsal

Back 21

rostral – toward front of brain
caudal – toward back of brain
ventral – toward bottom of brain
dorsal – toward top of brain

Front 22

Define the following BELOW the neuraxis)
rostral
caudal
ventral
dorsal

Back 22

rostral – toward the cerebrum
caudal – toward the bottom of the spinal cord
ventral – toward the front
dorsal – toward the back

Front 23

Tracts are named based on origin and termination. What are the origin/termination of the spinocerebellar & corticospinal tract?

Back 23

spinocerebellar:
origin- spinal cord
termination- cerebellum

corticospinal:
origin- cerebral cortex
termination- spinal cord

Front 24

Define afferent & efferent w/i the CNS:


*NOT the same as in PNS

Back 24

afferent= conducting TOWARD a structure
(red)

efferent= conducting AWAY from a structure
(green)

Front 25

Cerebrum
structure-
function-

Back 25

structure- consists of diencephalon & 2 cerebral hemispheres containing *gyri (ridges) & *sulci &f fissures* (valleys), outer laminar surface is referred to as cerebral cortex

function-complex processing of sensory info & formulation of volitional motor responses
* sensations must reach cerebral cortex to be CONSCIOUSLY perceived

Front 26

T/F

Like the PNS, groups of neurons w/i the CNS are called ganglia

Back 26

FALSE

called nuclei w/i the CNS

Front 27

*The internal fluid (CSF) filled spaces of the cerebrum are __________

Back 27

ventricles

*ventricles secrete CSF which "floats" brain w/i cranial cavity for protection & circulates over the brain & spinal cord & empties into the bloodstream via VENOUS SINUSES

Front 28

The cortex & nuceli are rich in neuronal cell bodies are referred to as ___________

Back 28

gray matter (darker)

Front 29

Areas under the cortext w/ collections of tracts/fasiculi are rich in myelinated axons are are referred to as ____________

Back 29

white matter (lighter)

Front 30

*What are the 2 main white matter structures w/i the cerebrum & what are their functions?

Back 30

1. corpus collosum (GREEN)- major pathway for axons crossing btwn cerebral hemispheres

2. internal capsule (BLUE)- major pathway btwn cerebral hemispheres & more caudal structures (brainstem, spinal cord, thalmus, etc)

Front 31

Gyri (RED) and sulci (BLUE) can be seen above. What are the deeper, more consistent sulci (PURPLE) called?

Back 31

fissures

Front 32

*What do the primary fissures divide the cerebrum into?

Back 32

functional "lobes"

*areas of similar function are located near one another

Front 33

*What is a collection of neurons that forms the laminar structure on the surface of the cerebrum?

Back 33

cortex

Front 34

Give the structure/function of the following major nuclear group w/i the cerebrum:

*thalmus

Back 34

structure-
part of diencephalon

function-
somatic info
sensation & motor function

Front 35

Give the structure/function of the following major nuclear group w/i the cerebrum:

*hypothalmus

Back 35

structure-
w/i diencephalon

function-
ANS regulation

Front 36

Give the structure/function of the following major nuclear group w/i the cerebrum:

*basal ganglia

Back 36

structure-
group of nuclei, associated structures include caudate nucleus, putamen, globus, pallidus, subthalmic nucleus, & substantia nigra

function-
motor procession

Front 37

Give the structure/function of the following major nuclear group w/i the cerebrum:

*hippocampal formation

Back 37

structure-
located in medial temporal lobe on each side

function-
consolidation of memory

Front 38

Cerebellum
*structure-
*function-

Back 38

structure (ORANGE)- 2 hemispheres & vermis, attached to posterior aspect of brainstem, surface more densely convoluted than cerebral cortex (cerebrum)

function- uses complex sensory info UNCONSCIOUSLY to COORDINATE motor activity

Front 39

Brainstem
*structure-
*function-

Back 39

structure (BLUE)- contains tracts btwn spinal cord & brain, neurons for both somatic motor & parasympathetic (ANS) output, modulates control of respiration, HR, & other autonomic functions

function- CNS interface with PNS (cranial nerves), provides first order processing of primary sensation & hearing, vestibular, taste
*motor & sensory functions of the head & autonomic control of some body functions*

Front 40

Which component of the CNS is referred to as a "primitive brian"?

Back 40

brainstem

Front 41

What are the 3 divisions of the brainstem & what are their functions/locations?

Back 41

1. midbrain
(f) eye movement control, CN 3 & 4
(l) rostral most part of brainstem (RED)

2. pons
(f) communication btwn cerebrum & cerebellum, CN 5, 6, 7, & 8
(l) middle portion of brainstem (GREEN)

3. medulla
(f) conscious reticular formation, autonomic control (heart rate & breathing), CN 9, 10, 11, & 12
(l) caudal most part (PURPLE)

Front 42

Spinal Cord
structure-
*function-

Back 42

structure (YELLOW)- along spine

function- primary interface for CNS w/ body via peripheral nerves, sends & receives info from brain via axons (tracts)
*major tracts that convey info btwn brain & body

Front 43

What do neurons contained in the spinal cord do (3 things)?

Back 43

1. receive primary somatic SENSORY info
2. directly & indirectly modulate MOTOR activity of muscles
3. modulate AUTONOMIC activity of viscera