Nervous System

Question 1

Functions

Answer 1

sensory input, integration, motor output, cognition, emotion, arousal

Question 2

Nervous System Cells

Answer 2

2 types: neuron and glial cell

Question 3

Neuron

Answer 3

basic functional cell of the nervous system

Question 4

Role of neuron

Answer 4

process and transmit information through chemical and electrical signaling

Question 5

Glial (neuroglial)

Answer 5

smaller, outnumber neurons, do not participate in signaling but are essential to function

Question 6

Role of glial cells

Answer 6

repair neuron after injury, maintain proper ionic environment, modulate electrical conduction

Question 7

Neuron parts

Answer 7

soma, dendrite, axon, axon hillock

Question 8

Soma

Answer 8

cell body

Question 9

Dendrite

Answer 9

branched projection of neurons, receives synaptic input from other neurons

Question 10

Axon

Answer 10

nerve fiber, long projection of the nerve cell that conducts electrical impulses away from the soma

Question 11

Axon hillock

Answer 11

part of the soma that connects to the axon, where synaptic signals are summed before being transmitted

Question 12

Multipolar Neurons

Answer 12

on axon, many dendrites, allows a lot of information to be received and integrated. ex: motor cells

Question 13

Bipolar Neurons

Answer 13

have two projections, axon on one side and dendrite on the other. ex: special senses, retina of eye

Question 14

Unipolar/pseudounipolar

Answer 14

start bipolar, then become unipolar, sit in dorsal root ganglia. ex: general sensory stuff

Question 15

Gray vs. White Matter

Answer 15

gray: neurons, outside
white: axons, inside. Axons are myelinated, myelin is white, thus the “white” matter. Opposite in spinal cord

Question 16

CNS

Answer 16

brain and spinal cord

Question 17

PNS

Answer 17

peripheral nerves, connects CNS to rest of body

Question 18

Cerebral cortex lobes

Answer 18

plans and executes activity and movements. central sulcus divides the frontal and parietal lobe.

Question 19

Solci

Answer 19

depressions

Question 20

Gyri

Answer 20

upper folds

Question 21

Homonculus

Answer 21

little person, the amount of tissue devoted to a given body area, and is proportional to how richly integrated it is. Right side of homonculus controls left side of body, and left homonculus controls right side of body

Question 22

Cranial nerves

Answer 22

come out of brain stem and do stuff for your face

Question 23

conus medullaris

Answer 23

where spinal cord ends around L1, shaped like a cone

Question 24

cauda equina

Answer 24

innervations coming off and into respective segments

Question 25

filum terminale

Answer 25

connective tissue that come from conus medullaris down into tailbone

Question 26

spinal cord

Answer 26

in cervical and thoracic vertebrae there is more white matter, but as you get down into lumbar, there is more gray matter. As you go down, less white (myelin) because there is less distance to travel

Question 27

dorsal (posterior) root

Answer 27

afferent (sensory)

Question 28

ventral (anterior) root

Answer 28

efferent (motor)

Question 29

spinal nerve

Answer 29

where ventral and dorsal root meet. Here it exits the vertebral column and splits into two rami.

Question 30

rami

Answer 30

contain both sensory and motor info. Dorsal and ventral rami

Question 31

dorsal rami

Answer 31

supply the back

Question 32

ventral rami

Answer 32

supply the limbs and anterolateral trunk. Only these rami enter into formation of nerve plexi

Question 33

Pathway

Answer 33

rootlet, root, spinal nerve, rami

Question 34

Spinal nerves

Answer 34

C: 8, T: 12, L: 5, S: 5, Coccygeal: 1

Question 35

Positioning

Answer 35

spinal cord descends in space between vertebral bodies and articular processes. The rami come out of the intervertebral foramen

Question 36

Which rami enter into formation of the nerve plexi?

Answer 36

ventral rami only

Question 37

Nerve plexus

Answer 37

network of intersecting nerves, combine ventral rami of spinal nerves into one nerve, both motor and sensory nerves

Question 38

Why nerve plexus?

Answer 38

protection in the event of an injury: if one spinal nerve was ever cut, you don't lose innervation to that area, because you have others in that plexus.

Question 39

Brachial plexus

Answer 39

formed by nerves C5-T1, supplies upper extremity

Question 40

Lumbosacral plexus

Answer 40

lumbar plexus formed by nerves L1-L4, goes to front of leg sacral plexus formed by nerves L4-S3, goes to back of leg supplies lower limbs

Question 41

Dermatome

Answer 41

area of skin innervated by afferent fibers of a single spinal nerve. Basically a skin bet of sensory innervation. Overlap for similar reasons to plexi

Question 42

Adjacent dermatomes

Answer 42

overlap so that if one nerve is sectioned, the area will not completely lose sensation

Question 43

Cutaneous vs. dermatome innervation

Answer 43

dermatomes are isolated, while the cutaneous innervation is combined. Dermatome is spinal level (i.e. herniated disc), cutaneous is peripheral level (more broad)

Question 44

PNS Subdivisions

Answer 44

somatic and visceral, both are motor (efferent) and sensory (afferent)

Question 45

Somatic

Answer 45

consists of nerves that carry conscious sensation from peripheral regions back to CNS, nerves that innervate voluntary muscle. Involved with receiving and responding to information from external environment

Question 46

Visceral

Answer 46

consists of nerves that monitor changes in viscera, nerves that innervate smooth muscle, cardiac muscle, and glands. Involuntary, detect and respond to information from internal environment

Question 47

Autonomic nervous system

Answer 47

part of visceromotor, includes sympathtic and parasympathetic. Affects heart and respiratory rate, pupil dilation, perspiration, and sexual arousal. Mostly involuntary, but can have some degree of conscious control (i.e. swallowing)

Question 48

Sympathetic

Answer 48

fight or flight, quick response mobilizing system

Question 49

Parasympathetic

Answer 49

rest and digest, more slow acting dampening system, but is not totally inhibiting