FINAL EXAM Flashcards

1
Q

Define Nissl body

A

well developed rough ER, involved in metabolic activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Do primary brain tumors originate from NEURONS in the brain or the SUPPORTING CELLS?

A

Supporting cells (neuroglial cells). 1. neurons are amitotic and cannot divide 2. supporting cells are able to divide, and proliferate, causing tumor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why are neurons amitotic?

A

they do not contain centrioles, which are needed for cells to divide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the structural organization of a tract or nerve

A

(innermost –> outermost)

neuron –> endoneurium –> fascicle –> perineurium –> epineurium –> tract/nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

define Endoneurium

A

connective tissue that covers each axon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define tract

A

bundle of axons in the CNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Name and describe the function of supporting cells IN THE CNS (4)

A
  1. astrocytes: involved in forming the blood-brain barrier
  2. microglia: clean cell debris
  3. ependymal cells: beat cilia to move cerebrospinal fluid (CSF)
  4. oligodendrocytes: myelinates axons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Name and describe the function of supporting cells IN THE PNS (2)

A
  1. Schwann cells: myelinate axons, contain neurilemma
  2. Satellite cells: act as chemical barrier
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which part of a neuron is known as the secretory region and why?

A

Axon terminals because they release neurotransmitters into extracellular space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

define epineurium

A

connective tissue that covers the bundle of perineurium-covered fascicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

define nerve

A

bundle of axons in the PNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Define ganglion

A

cluster of neuron cell bodies in the Peripheral Nervous System (PNS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

define perineurium

A

connective tissue that covers fascicle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Define nucleus

A

cluster of neuron cell bodies in the Central Nervous System (CNS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which part of a neuron is known as the conducting region and why?

A

Axon because it generates and transmits action potentials away from the cell body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Which part of a neuron is known as the receptive center and why?

A

Dendrites because they receive and convey electrical signals towards the cell body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How many axons can each neuron have?

A

Each neuron can only have one axon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which part of a neuron is known as the biosynthetic center and why?

A

Cell body because all biosynthetic activities occur in the cell body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

define Nodes of Ranvier

A

spaces between adjacent myelin shealths

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

define neurilemma

A

outermost nucleated cytoplasmic layer of schwann cells that surrounds the axon of the neuron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

which type of supporting cells are involved in the formation of the Blood-Brain Barrier?

A

Astrocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the function of the Blood Brain Barrier

A
  • prevents brain and nerve cells from contact with blood
  • additional shock absorption and insulation
  • provides nutrients and oxygen to the brain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

explain why myelinated axons in the CNS do not regenerate when severed

A

they have no regeneration tube because neurilemma is not present. they are amitotic so they cannot replicate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

explain why axsons in the PNS can regenerate when severed

A

axons in the PNS have regeneration tube formed by the neurilemma from the schwann cell and nuclei to replicate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

why are impuses conducted faster in a larger myelinated axon and slower in a smaller unmyelinated axon?

A
  1. diameter of axon: larger axons transmit impulses faster because there is less resistance
  2. degree of myelination: myelinated axons transmit impulses faster because myelinated axons use saltatory conduction (faster) and unmyelinated axons use continous conduction (slower)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Describe the resting membrane potential

A

resting state with no movement, more Na+ ions outside, more K+ ions inside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

describe the depolarization phase of an action potential

A

Na+ influx (enters the cell)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

describe the repolarization phase of an action potential

A

K+ efflux (exits the cell), occurs after action potential is reached

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

describe the hyperpolarization phase of an action potential

A

more K+ efflux (exiting the cell) then return to Resting membrane potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what is the absolute refractory period and the relative refractory period of an action potential?

A
  • absolute refractory period: occurs when the sodium gates are still open (depolarization phase) and the neuron is unable to initiate a new action potential
  • relative refractory period: occurs when the sodium gates are closed (repolarization phase) and a strong stimulus causes initiation of a new action potential
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

how does the body differ between a strong stimulus and a weak stimulous?

A

more frequent action potentials indicate a strong stimulus

less frequent action potentials indicate a weak stimulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Name and describe the structural classes of neurons (3)

A
  1. Uni/psuedo polar: a single process extending from the cell body, divided into peripheral and central processes
  2. bipolar: two processes attached to the cell body (one dendrite, one axon); found only in eye, ear, and olfactory mucosa
  3. multipolar: many processes attached to the cell body (many dendrites, one axon)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

which structural class of neurons is most abundant in the body?

A

multipolar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

name and describe the functional classes of neurons (3)

A
  1. sensory (afferent) neurons: carry impulses toward the CNS
  2. motor (efferent) neurons: carry impulses away from the CNS
  3. association neurons (interneurons): conduct impulses within the CNS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

which functional class of neurons is most abundant in the body?

A

association neurons (interneurons) make up 90% of the nerves in the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

name and describe the types of nerve fibers (3)

A
  1. group A: largest diameter, heavily myelinated; transmits impulses at 150 m/s
  2. group B: intermediate diameter, lightly myelinated; transmits impulses at 15 m/s
  3. group C: smallest diameter, unmyelinated; transmits impulses at 1 m/s
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

which type of nerve fiber has the fastest conduction? why?

A

Group A fibers because they have the largest diameter, which allows for the lowest resistance during conduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

which type of nerve fiber has the slowest conduction velocity? why?

A

Group C fibers, because they have the smallest diameter and thus the highest resistance during conduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What happens to the conduction velocity when myelinated axons become demyelinated?

A

conduction velocity decreases because myelin insulate the axonal membrane which reduces the ability of current to leak out of the axon, thus increasing the distance along the axon that a current can flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Name the structures protecting the brain (4)

A

Cranium, Meninges, Cerebral Spinal Fluid, Blood Brain Barrier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Name the types of meninges (3)

A

Outermost –> Innermost

  1. Dura Mater: double-layered, tough and inflexible
  2. Arachnoid mater
  3. Pia mater
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

List where Cerebral Spinal Fluid is located both inside and outside the brain

A
  • Inside: two lateral ventricles (cerebral cortex), third (diencephalon) and fourth (pons + medulla oblongata) ventricle
  • outside: subrarachnoid space
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Where is the location of the interventricular foramen?

A

connects the paired (2) lateral ventricles with the third ventricle at the midline of the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

give the location of the cerebral aqueduct

A

connects the third ventricle in to the fourth ventricle within the midbrain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What supporting cell lines the ventricles of the brain and what is its function?

A

ependymal cells, function is to circulate cerebrospinal fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What are the four regions of the brain

A

Cerebrum, Cerebellum, Diencephalon, Brainstem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Define gryus

A

the ridge (raised area) of wrinkled gray matter in the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

define sulcus

A

the grooves between two gyri

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

define fissure

A

the deeper sulcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

define corpus callosum

A

the pathway for communication between the two hemispheres of the cerebral cortex, located deep within the cerebrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

define gray matter

A

The region of the brain with many cell bodies and dendrites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Define white matter

A

the region of the brain with many axons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

define commissural tract

A

enables the two sides of the cerebrum to communicate with each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

define projection tract

A

transmit impulses from the cerebrum to parts of the lower brain and spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

define association tract

A

connect areas of the cerebral cortex within the SAME hemisphere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

what type of tract is the corpus callosum

A

commisural

57
Q

what type of tract is the arcuate fasciculus?

A

association

58
Q

what type of tract is the pyramidal tract?

A

projection

59
Q

name the 5 lobes in the cerebral hemisphere

A

Frontal, parietal, occipital, temporal, insula

60
Q

which lobe in the cerebral hemisphere cannot be viewed on the external surface?

A

Insula

61
Q

Name the sulci that separate the cerebral lobes (3)

A
  • Central sulcus: separates frontal and parietal
  • Lateral sulcus: separates frontal + parietal from temporal
  • Parieto-occipital sulcus: separates parietal and occipital
62
Q

name the functional areas of the cerebral cortex (3)

A

Motor, sensory, association

63
Q

Name and describe the function of the four motor areas of the frontal lobe

A
  • primary: voluntary movement of skeletal muscles
  • premotor: repitition and memory
  • frontal eye: eye muscle movement
  • Broca’s Area: speech
64
Q

what is the significance of the precentral gyrus

A
  • structure on the surface of the frontal lobe called the primary motor area
  • controls the voluntary movements of skeletal muscles
65
Q

discuss the contralateral control of voluntary skeletal muscle movements by the cerebral cortex

A

the right side of the body is connected to the left side of the brain and the left side of the body to the right side of the brain

66
Q

what would be the consequence of damage to the precentral gyrus in the left cerebral hemisphere?

A

degeneration of left pyramidal tract, loss of voluntary skeletal muscle movements on right side (right side paralysis)

67
Q

What would be the consequence of damage to the postcentral gyrus in the right cerebral hemisphere?

A

loss of sensation in the left side of the body

68
Q

what would be the consequence of damage to the Broca’s area

A

inability to speak

69
Q

What is Broca’s aphasia

A

inability to speak or communicate verbally

70
Q

What is Wernicke’s aphasia?

A

“word salad”; random, nonensical, or incoherent sound or speech

71
Q

Why can right side paralysis be sometimes accompanied by Broca’s aphasia?

A

Broca’s area is only on the left frontal lobe. right side paralysis occurs from left side cerebral brain damage

72
Q

what would be the consequence of damage to the right postcentral gyrus?

A

Somatosensory damage (homunculus); left side loss of sensation

73
Q

Name and describe the function of the (3) main cerebral basal nuclei

A
  1. caudate nucleus: motor and behavioral functions
  2. putamen: motor function and physical movement, skeletal muscle innervation
  3. globus pallidus: voluntary movement regulation
74
Q

What is the pathogenesis of Parkinson’s disease?

A

damage to the domapinergic neurons

75
Q

Why is L-DOPA is used to manage Parkinsons disease and not dopamine?

A

L-DOPA is nonpolar and a precursor to dopamine. L-DOPA can cross the BBB to reach the basal nuclei and convert into dopamine. Dopamine is polar and cannot cross the BBB

76
Q

Which area in the diencephalon is referred to as the “gateway to the cerebral cortex”? Why?

A

thalamus because all sensory input must stop in the thalamus before projecting to their respective cerebral cortex

77
Q

name two areas in the diencephalon with endocrine function

A

Epithalamus and Hypothalamus

78
Q

structurally, how is the brain stem similar to the spinal cord?

A

Brain stem is continuous with the spinal cord

they both contain tracts

79
Q

Name the parts of the brainstem (3)

A

Midbrain

Pons

Medulla Oblongata

80
Q

What are the corpora quadrigemina and what are their functions

A

four colliculi

  • two inferior: visual reflex center
  • two superior: auditory reflex center
81
Q

name and give the functio of the (2) pigmented nuclei in the midbrain

A
  • red nuclei: contrl limb flexion
  • substantia nigra: sends dopaminergic neurons to basal nuclei to control voluntary movement
82
Q

how many of the cranial nerves have cell bodies located in the brain stem?

A

10 of 12 cranial nerves (CN3-CN12)

(all except olfactory and optic)

83
Q

explain why trauma to the brain stem can be fatal

A

damage to the brainstem = no signals to/from brain = no function of involuntary organs (heart, lungs, etc) = death

84
Q

where does the decussation of the pyramids occur and what is the function?

A

decussation of the pyramids affects contralateral control, occurs over the anterior fissure of the medulla oblongata

85
Q

define arbor vitae

A

network of white matter within gray matter of cerebellum

86
Q

define vermis

A

prominent ridge along the midline of the cerebellum; hold cerebral hemispheres together medially; also called spinocerebellum

87
Q

name the cerebellar lobe that cannot be viewed on the surface of the hemisphere

A

flocculondular lobe

88
Q

the inability to maintain balance during a tandem walk (heel to toe) due to alcohol intoxication is indicative of impairment of which brain region

A

cerebellum

89
Q

describe the arrangement of the gray matter and the white matter in the cerebellum and cerebrum as well as the brainstem and spinal cord

A
  • Cerebellum and cerebrum: inner white matter, outer gray matter
  • brainstem and spinal cord: inner gray matter, outer white matter
90
Q

define spinal dural sheath

A

single layered dura mater; has a space between internal surface of vertebral column and dura mater (epidural space)

91
Q

define filum terminale

A

part of the pia mater that supports the spinal cord VERTICALLY

92
Q

Define denticulate ligaments

A

part of the pia mater that supports the spinal cord LATERALLY

93
Q

Define epidural space

A

supports underneath the dura mater layer

94
Q

define subarachnoid space

A

supports underneath the arachnoid mater layer; contains cerebral spinal fluid

95
Q

define central canal

A

runs length of spinal cord and contains cerebral spinal fluid

96
Q

How do the dura mater and pia mater surrounding the spinal cord differ from the dura mater and pia mater surrounding the brain

A

Dura mater surrounding the brain is double layered; dura mater surrounding the spinal cord is single-layered

Pia mater surrounding the brain is delicate and attached to the surface of the brain; pia mater surrounding the spinal cord is strong and anchors the spinal cord both vertically and laterally

97
Q

What medical condition results from degeneration of nuclei in the ventral horns in the spinal cord?

A

Amyotrophic Lateral Sclerosis (ALS)

98
Q

transection (damage) of the spinal cord above the cerivical enlargment can cause

A

quadriplegia (damage to all limbs)

99
Q

How can you tell the difference between paralysis caused by damage at the level of the precentral gyrus and damage at the spinal cord?

A
  • Damage at the precentral gyrus: hemi-paralysis, causing one side of the body to be paralyzed
  • damage at the spinal cord: limb paralysis
100
Q

Autonomic Nervous System function

A

takes information to the smooth muscles and cardiac muscles (soft organs)

101
Q

Somatic Nervous System function

A

Takes information to the skeletal muscles (hard organs)

102
Q

list the sensory receptors (4)

A

somatosensory

mechanoreceptors

chemoreceptors

photoreceptors

103
Q

Activation of which division of the Autonomic Nervous System causes dilation of the pupils?

A

sympathetic

104
Q

Activation of which division of the Autonomic Nervous System causes constriction of the pupils?

A

parasympathetic

105
Q

list (3) major parts of the eye

A

Tri-layered eye wall

humors

lens

106
Q

What is the function of the lens in the eye?

A

Reflect and refract light from cornea at the front of the eyeball to the photoreceptors at the back of the eyeball (with the retina)

107
Q

name and describe the (3) layers of the wall of the eye

A
  1. fibrous outer layer: avascular dense regular connective tissue
  2. vascular middle layer: composed of anterior iris, middle ciliary body, and posterior choroid
  3. sensory inner layer: confined to back of eye (fundus), avascular
108
Q

what structure forms the most anterior part of the eye?

A

Cornea

109
Q

location and function of the sclera

A

back whites of eyes posterior 5/6 of eye

110
Q

location and function of the cornea

A

front clear of eye, anterior 1/6 of eye

111
Q

location and function of the pupil

A

center of eye, allows light to enter eye

112
Q

location and function of rods

A

black and white vision, dim light

113
Q

location and fuction of cones

A

color vision, bright light

114
Q

location and function of suspensory ligament

A

holds lense in place

115
Q

location and function of optic disc

A

where the optic nerve runs from back of eyeball (blindspot)

116
Q

location and function of macula lutea

A

used for hard focus

117
Q

location and function of fovea centralis

A

contains ONLY cones; at center f macula lutea’ has highest visual acuity

118
Q

visible colored part of the eye

A

iris

119
Q

what are the two humors in the eye and their functions?

A
  1. aqueous humor: provides nutrients to avascular cornea/lense; located in anterior segment of eye
  2. vitreous humor: supports lense and compresses neural layer against pigmented layer; located in posterior segment of eye
120
Q

which humor in the eye is formed and drained throughout life?

which humor is formed during embryonic development only?

A

formed and drained throughout life: aqueous

formed during embryonic development only: vitreous

121
Q

name and describe the two layers of the sensory layer

A

outer pigmented layer: absorbs light and develops a clear image

inner neural layer: (aka retina) contains photoreceptors, bipolar neurons, and ganglion neurons

122
Q

name the two types of photoreceptors; which type is more sensitive to light?

A

rods and cones

rods are moresensitive to light

123
Q

what happens when right optic nerve is severed?

what happens when right optic tract is severed?

A

severed optic nerve: right side blindness

severed optic tract: loss of sight in the left visual field

124
Q

what happens when the right primary visual cortex in the right occipital lobe is damaged?

A

partial blidness in both eyes

(primary visual cortex controls both eyes)

125
Q

What is retinal detachment? Explain how retinal detachment can lead to blindness.

A

When retina separates from blood vessels of the eyeball. Causes blurry vision, incorrect visual signals. The continuous loss of sight will eventually lead to blindness.

126
Q

location and function of the

  • lateral geniculate nucleus (LGN)
  • supoerior colliculi
  • primary visual cortex
A
  • lateral geniculate nucleus: thalamus, visual relay center of brain
  • superior colliculi: upport part of the corpora quadrigemina, visual reflex control center
  • primary visual cortex: occipital lobe, controls sight ability
127
Q

pathway of light through the eye from the cornea to the photoreceptors

A

cornea –> aqueous humor –> pupil –> lens –> vitreous humor –> retina –> photoreceptors

128
Q

the axons of which type of neurons in the retina form the optic nerve and generate/transmit action potentials?

A

ganglion cells

129
Q

what is myopia and what type of lense is used to correct it?

what is hyperopia and what type of lense is used to correct it?

A

myopia = nearsightedness, concave lense

hyperopia = farsightedness, convex lense

130
Q

list the three major parts of the ear

A

external ear

middle ear

internal ear

131
Q

name the (3) auditory ossicles in the middle ear

A

Malleus (tympanic membrane)

Incus

Stapes (oval window)

132
Q

name the (3) parts of the bony labyrinth

A

vestibule

semicircular canals

cochlea

133
Q

what part of the ear determines loudness?

what part of the ear determines pitch?

A

loudness = basilar membrane

pitch = cochlear sterocilia

134
Q

(3) types of cells in a taste bud

A

basal cells

supporting cells

gustatory cells

135
Q

in which cerebral lobe is the primary gustatory cortex located?

A

insula

136
Q

name and describe the (3) chemical classes of hormones

A
  1. Biogenic amine hormones: derived from TYROSINE; polar, bind to membrane receptors
  2. peptide/protein/glycoprotein hormones: composed of several amino acids; polar, bind to membrane receptors
  3. steroid hormones: derived from CHOLESTEROL; non-polar, bind to intracellular receptors
137
Q

name and describe the (2) types of hormone receptors

A
  1. membrane receptors: on the plasma membrane surface
  2. intracellular receptors: within the cytoplasm
138
Q

name and describe the (4) hormone INTERACTIONS with receptors

A
  1. Classical endocrine interaction: endocrine gland realease hormone into boodstream which transports it to target cell
  2. Paracrine interaction: endocrine cell release hormone into interstitial fluid surrounding target cell
  3. Juxtacrine interaction: endocrine cells are juxtaposed to the target cells in the same organ
  4. Autocrine interaction: endocrine cells release hormone are the target cells