Hesi A2 Nervous System

Front 1

In the PNS what is the myelin sheath composed of

Back 1

schwann cells

Front 2

where are the schwann cells and myelin sheath located

Back 2

axon

Front 3

In the CNS what are the sheaths composed of

Back 3

oligodendrocytes

Front 4

how are white and grey matter distinguishedd

Back 4

the myelin sheath

Front 5

white matter contains what

Back 5

myelinated axons of neurons

Front 6

gray matter contains what

Back 6

unmyelinated portions of the neurons

Front 7

how is polarization established what is outside what is inside

Back 7

by maintaining NA+ outside of the cell and K inside

Front 8

resting membrane is more permeable to what

Back 8

potassium

Front 9

resting membrane what happens

Back 9

more potassium ions leak out of the cell than sodium going into the cell

Front 10

what three things force gated channels respond

Back 10

to neurotransmitters, membrane potential shift, or other stimuli

Front 11

resting potential is what

Back 11

unstimulated polarized state of a neuron

Front 12

what is a graded potential

Back 12

the change in resting potential of plasma membrane

Front 13

how does the graded potential start

Back 13

the change in resting potential is because of a stimulus

Front 14

what does a graded potential cause the gates to do

Back 14

open the channels so either Na or K enters or exits

Front 15

when sodium ions enter the membrane becomes

Back 15

depolarized

Front 16

when the membrane is depolarized it is what charge

Back 16

positive

Front 17

if the stimulus opens the K channels what type of polarizations is it

Back 17

hyperpolarization

Front 18

how does hyperpolarization effect the membrane's charge

Back 18

becomes negative

Front 19

what is the cell body of a neuron called

Back 19

soma

Front 20

what is the rough endoplasmic reticulum in the soma called

Back 20

Nissl bodies

Front 21

what is the cytoplasm of the axon

Back 21

axoplasm

Front 22

what is the plasma membrane of a axon

Back 22

axolemma

Front 23

sensory neurons are also called

Back 23

afferent

Front 24

what do sensory/afferent neurons do

Back 24

transmit sensory impulses from the skin to the CNS

Front 25

Motor neurons are also called

Back 25

efferent

Front 26

motor/efferent neurons do what

Back 26

transmit nerve impulses from the CNS to effectors or target cells

Front 27

what are the3 categories of effectors

Back 27

muscles glands organs

Front 28

what do interneurons do

Back 28

transmit impulses from sensory neurons to motor neurons

Front 29

where are the interneurons located

Back 29

CNS

Front 30

what are gyrus

Back 30

elevated ridge

Front 31

what is a sulcus

Back 31

a shallow groove

Front 32

what is a fissure

Back 32

deep groobe

Front 33

the cerebral cortex is
-composed of what type of neurons
-what color
and forms what part

Back 33

thin outer layer-the layer of unmyelinated neurons (the grey matter) forming the cortex of the cerebrum

Front 34

what color is the cerebral cortex

Back 34

gray matter

Front 35

what is control from the cerebral cortex

Back 35

speech, evaluation of stimuli, conscious thinking, skeletal muscles

Front 36

where is the cerebral white matter

Back 36

underneath the cerebral cortex

Front 37

what connects the cerebrum to the brainstem

Back 37

diencephalon

Front 38

pain, pressure, sensitivity to temperature are evaluated here before cerebrum

Back 38

thalamus

Front 39

epithalamus contains what gland

Back 39

pineal gland

Front 40

what does the pineal gland secrete

Back 40

melatonin

Front 41

who is responsible for sleep cycle

Back 41

the pineal gland inside the epithalamus

Front 42

what does the hypothalamus regulate

Back 42

autonomic nervous system, emotion, behavior hunger thirst body temperature and clock

Front 43

what two hormones does the hypothalamus produce

Back 43

antidiuretic and oxytocin

Front 44

what is antidiuretic

Back 44

ADH

Front 45

what else does the hypothalamus release

Back 45

releasing hormones to the anterior pituitary gland

Front 46

the forebrain controls what

Back 46

motor, sensory, association

Front 47

what is located in the forebrain or prosencephalon

Back 47

thalamus, hypothalamus, pituitary, epithalamus, pineal gland

Front 48

where is the cardiovascular center and respiratory center located

Back 48

in the hindbrain or rhombocephalon

Front 49

somatic nervous system does what

Back 49

contraction of skeletal muscles

Front 50

autonomic nervous system controls what

Back 50

organs, glands, involuntary muscles

Front 51

autonomic nervous has two division

Back 51

sympathetic nervous system and parasympathetic

Front 52

sympathetic nervous system

Back 52

action. heart rate , sugar increase into blood,flight or fight response

Front 53

parasympathetic system activates

Back 53

tranquil functions like saliva or digestive enzymes

Front 54

how does the transmission of a nerve impulse occur

Back 54

along the neuron from one end to the other

Front 55

what is the result of of the electrical changes across the membrane of a neuron

Back 55

transmission of a nerve impulse

Front 56

what is the membrane of an unstimulated neuron like

Back 56

polarized

Front 57

what does polarized mean

Back 57

there is a difference of electrical charge between the outside and inside of a membrane

Front 58

what is the inside of a neuron charged when it is polarized

Back 58

the inside is negative the outside is positive

Front 59

resting membrane potential means the nerve is

Back 59

polarized

Front 60

multipolar neurons have how many axons versus dendrites

Back 60

one axon to numerous dendrites

Front 61

which is the most common neuron

Back 61

multipolar

Front 62

bipolar neurons have now many axons to dendrites

Back 62

one axon one dendrite

Front 63

what are bipolar neurons found as

Back 63

specialized sensory neurons

Front 64

what are the specialized sensory neurons

Back 64

eye ear olfactory

Front 65

what are unipolar neurons in respect to axon and dendrites

Back 65

two axons leading to the cell

Front 66

unipolar neurons are mainly what type of neuron

Back 66

senory neurons

Front 67

what is a nerve fiber

Back 67

an axon

Front 68

what is a bundle of nerve fibers

Back 68

a nerve

Front 69

where are nerves found

Back 69

pns

Front 70

what are cell bodues grouped into seperate bundles

Back 70

ganglia

Front 71

3 layers of the peripheral nerve

Back 71

epineurium
perineurium
endoneurium

Front 72

what does the epineurium cover

Back 72

outer layer that surrounds the entire nerve

Front 73

what does the perineurium cover

Back 73

bundles of axons

Front 74

what are bundles of axons called

Back 74

fascicles

Front 75

what surrounds each individual axon

Back 75

endoneurium

Front 76

what is a nerve tract

Back 76

bundle of nerve fibers

Front 77

where is the nerve tract found

Back 77

CNS

Front 78

which cell give the star shaped appearance

Back 78

astrocytes

Front 79

what do astrocytes do

Back 79

maintain the ion balance

Front 80

which cell controls the exchange of materials between blood vessels and neurons

Back 80

astrocytes

Front 81

what are the phagocytic macrophages in the nervous system

Back 81

microglia

Front 82

what cells line the fluid‐filled cavities of the brain and spinal cord. Many are ciliated.

Back 82

ependymal cells

Front 83

what do schwann cells do

Back 83

interrupt the continuous conduction of a nerve impulse

Front 84

axon potentials are only generater where

Back 84

at the nodes of ranvier

Front 85

describe salutatory conduction

Back 85

the appearance of nerve impulses jumping from node to node. because of the myelin sheath, they do not go accross that area.