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NBDE PART 1 BIOCHEM/PHYSIOLOGY > Nerves > Flashcards

Flashcards in Nerves Deck (312):
1

all cells have a resting potential t/f

true. ALL CELLS NOT just excitable cells have a resting potential.

2

resting potential means the interior/exterior is negative with respect to the other

interior

3

resting potential is _ in excitable cells

-70mV

4

name two excitable cells

muscle and neurons

5

in neurons the action potential is called

nerve impulse

6

as sodium flood the cell during initial depolarization the membrane potential can reach as high as

+55mV (inside positive)

7

depolarization is reducing or increasing the charge across the membrane

reducing

8

threshold voltage is

-50mV

9

neurilemma

aka sheath of Schwann/Schwann's membrane or neurolemma = thin membrane spirally enwrapping the myelin layers of certain fibers especially those of the PERIPHERAL NERVES, or the axons of UNMYELINATED NERVE FIBERS

10

all axons of the (CNS/PNS) have a sheath of Schwann cells (neurilemma)

PNS only. CNS does not have neurilemma = this is why regeneration of these severed axons is more difficult

11

in the CNS myelin sheaths are called

oligodendrocytes

12

right sided lesions of the spinal cord result in loss of motor activity on the _ side, and pain and temperature sensations on the __ side

lose motor activity on the SAME (ipsilateral) side, and pain and temperature lost on the opposite side (contralateral)

13

the primary action of local anesthetics in producing a conduction block is to decrease the permeability of the ion channels to __ions

sodium.

anesthetic will displace the calcium ions from the sodium channel receptor site allowing synesthetic molecule to bind the site, blocking the sodium channels ==> decrease sodium conductance ==> decreases rate of electrical depolarization --> fail to reach threshold potential level so no propagated AP = called CONDUCTION BLOCKADE

14

nerve block produced by local anesthetics is called

non-depolarizing nerve block

15

local anesthetics reversibly/irreversibly block nerve impulse conduction

reversibly = therefore loss of sensation at site.

16

the site of action of local anesthetics is at the ___ of the nerves

lipoprotein sheath

17

local anesthetics are effective on?

free nerve endings and on axons

18

which are affected first by local anesthetics:
skeletal muscle tone, proprioception, touch myelinated nerve fibers

small, myelinated nerve fibers which conduct pain and temperature are affected FIRST. followed by touch, proprioception and skeletal muscle tone

19

emergence from a local anesthetic nerve bock follows the same diffusion patterns as induction does except in

reverse order

20

recovery from local anesthesia is usually slower/faster process than induction because the anesthetic is bound to the drug receptor site in the sodium channel and therefore is released more ___ than absorbed.

slower
slowly

21

when a local anesthetic is given which conductance is changed and which are not affected: Calcium/chloride/potassium/sodium

only sodium changes!

22

what is the function of the lateral spinothalmic tract:

a. discriminating touch and pressure sensations
b. unconscious kinesthesia
c. pain, temp, and crude touch;opposite side
d. crude touch and pressure

lateral spinothalmic =
pain, temp, and crude touch; opposite side

23

what is the function of the anterior spinothalmic tract

a. discriminating touch and pressure sensations
b. unconscious kinesthesia
c. pain, temp, and crude touch;opposite side
d. crude touch and pressure

crude touch and pressure = anterior spinothalmic

24

function of anterior and posterior spinocerebellar tract

a. discriminating touch and pressure sensations
b. unconscious kinesthesia
c. pain, temp, and crude touch;opposite side
d. crude touch and pressure

unconscious kinesthesia

25

function of fasciculi gratis and cuneatus

a. discriminating touch and pressure sensations
b. unconscious kinesthesia
c. pain, temp, and crude touch;opposite side
d. crude touch and pressure

discriminating touch and pressure sensations

26

the white/gray matter of the spinal cord contains tracts that travel up and down the spinal cord

white

27

_tracts are sensory

ascending

28

_ tracts are motor

descending

29

you can tell by the name of tract if they are ascending or descending (usually). most ascending tracts start with "spino" indicating origin in the spinal cord and name ends with the part of the brain that the tract leads to. for example the spinothalmic tract travels from where to where?

spine to thalamus

30

1. tracts whose names begin with a part of the brain are __

motor

31

is the corticospinal tract motor/sensory

motor (it starts with a part of the brain-cerebrum) and goes down towards motor neurons in the cord.

32

the origin of a spinal tract refers to the

location that the cell body of the tract lies

33

the termination of a spinal tract refers to

where the axon terminates

34

spatial summation occurs when two excitatory inputs arrive at a postsynaptic neuron in rapid succession or simultaneously?

at the same time (simultaneously)

35

neurotransmitters that are EXCITATORY will increase the probability of causing an

action potential in the postsynaptic neuron = an excitatory postsynaptic potential (EPSP)

36

neurotransmitters that are INHIBITORY will decrease the probability of causing an

action potential in the postsynaptic neuron = an inhibitory postsynaptic potential (IPSP)

37

Can the same NT be excitatory to one receptor and inhibitory effect on another?

yes

38

there are 2 forms of summation by which EPSPs may combine to reach threshold and initiate an AP: called?

temporal and spatial summation

39

in spatial summation two excitatory inputs (from multiple presynaptic fibers) arrive at a postsynaptic neuron in rapid simultaneously and produce a greater

depolarization

40

in temporal summation 2 excitatory inputs arrive at post synaptic neuron in __

rapid succession

41

in temporal summation 2 excitatory inputs arrive at post synaptic neuron in rapid succession. this causes an increase in

the FREQUENCY OF NERVE IMPULSES in a single presynaptic fiber

42

if an AP is initiated at the midpoint along the length of an axon it will spread towards the

cell body (soma) and nerve endings

43

Saltatory conduction occurs in _ neurons only

myelinated

44

Saltatory conduction: conduction is faster/slower?
consumes more or less energy?

faster and consumes LESS energy
100 meters/second

45

Continuous conduction (the opposite of salutatory conduction) occurs in _ nerves

unmeylinated, relatively SLOW (1.0meter/sec)

46

T/F the myelin sheath decreases membrane capacitance and increases membrane resistance preventing movement of sodium and potassium through the membrane

true

47

salutatory conduction is of value of value for 2 reasons:
1. increases _ of nerve transmission
2. __energy for the axon bc ONLY THE NODES OF RANVIER DEPOLARIZES

1. velocity
2. conserves

48

conduction velocity depends on diameter and presence of nerve myelin sheath. the larger/smaller the diameter of a nerve the faster the conductance velocity.

larger diameter = faster = bc reduces resistance to flow


smaller diameter = slower

49

T/F in most cases acetylcholine has an inhibitory effect

false. AcH is most often an EXCITATORY NT

50

T/F GABA is believed to ALWAYS cause inhibition

true

51

excitatory NT's from the presynaptic membrane opens channels in the postsynaptic membrane that leads to an increase in the concentration of ___ w/in the postsynaptic cell and a decrease of __ ions.

increase sodium
decrease potassium = this leads to depolarization of the postsynaptic cell which is propagated further along the cell membrane by an AP

52

inhibitory NT's encourage _ of the postsynaptic cell, making it less likely to generate an AP

hyperpolarization

53

hyperpolarization created by inhibitory NT's is achieved by either increasing the flow of __ ions out of the cell or increasing __ ions into the cell.

increasing Cl- into the cell
or increasing K+ out of the cell
= both ways make the inside of the cell more negative

54

if GABA bind a GABA A receptor which occurs: increasing Cl- into the cell
or increasing K+ out of the cell

GABA A = Cl- flow into the cell

55

if GABA bind a GABA B receptor which occurs: increasing Cl- into the cell
or increasing K+ out of the cell

GABA B = K+ out of the cell

to remember (think A is closer to Cl-) than and B is closer to K)

56

whether a NT acts in an excitatory or inhibitory manner is determined by

the kind of receptor it binds-not the NT!!!

57

where does AcH act as an inhibitor?

inhibition of the heart by the vagus nerves

58

Norepinephrine usually act as excitatory/inhibitory?

usually act as excitatory

59

Dopamine usually act as excitatory/inhibitory?

inhibitory

60

serotonin usually act as excitatory/inhibitory?

inhibitor of pain pathways in spinal cord and brain

61

1. glutamate is ALWAYS excitatory/inhibitory?
2. GABA is ALWAYS excitatory/inhibitory?
3. glycine is ALWAYS excitatory/inhibitory?

1. excitatory
2. inhibitory
3. inhibitory

62

nitric oxide = changes intracellular that modify neuronal __ for seconds, minutes or longer

excitability

63

Monamine oxidase (MAO) is an enzyme that CATALYZES the oxidative DEAMINATION of monoamines such as

NE, serotonin, and epinephrine

64

deamination by Monamine oxidases(MAO) is helpful because it

metabolizes excess neurotransmitters that may build up at postsynaptic terminals

65

Parkinson's disease affects which part of the brain

basal ganglia

66

basal ganglia is important for controlling _ movement and establishing _

voluntary movement and establishing posture

67

Huntington's disease affects which part of the brain

basal ganglia

68

when the ___ altered the person has unwanted movements ex. involuntary jerking, spasm movements of facial muscles

basal ganglia
Huntington's disease
Parkinson's disease

69

the striatum of the basal ganglia refers to what 2 nuclei?
caudate
putamen
globus pallidus

caudate nucleus and putamen = striatum

70

striatum gets its name bc it appears

striated

71

lentiform nucleus is the combo of what basal ganglia nuclei?

caudate
putamen
globus pallidus

putamen and globus palidus

72

1. putamen and globus palidus
2. putamen and caudate nucleus

1. putamen and globus palidus =Lentiform nucleus
(to remember look at the word Lentiform (L) = gLobus paLLidus
2. caudate and putamen = striatum

73

basal ganglia and cerebellum = large collections of nuclei that modify movement. they communicate to each
other via the ___ and what neurotransmitter?

thalamus
dopamine
via a direct and indirect path

74

1. output of cerebellum is excitatory or inhibitory?
2. output of basal ganglia is excitatory or inhibitory?

1. excitatory
2. inhibitory

75

the cerebellum is __ to the cerebrum

posterior

76

cerebellum is above/bellow the pons and medulla

above

77

cerebellum is divided into

2 lateral hemispheres and a middle portion

78

2 functions of cerebellum

maintain equilibrium and muscle coordination

79

the major parts of the extrapyramidal system are the subcortical nuclei which are the?

basal ganglia nuclei

80

the two classes of AcH receptors in autonomic ganglia

nicotinic and muscarinic

81

main type of neuron in autonomic ganglia

postganglionic

82

the classic NT of autonomic ganglia whether sympathetic or parasympathetic is

AcH

83

Nicotinic receptors are stimulated by:
AcH/nicotine/muscarine

AcH and nicotine
NOT MUSCARINE

84

nicotinic receptors are found at _ ganglionic synapses and at neuromuscular junctions and adrenal medulla.

all

85

nicotinic receptors produce excitation and a __ EPSP which causes ion channels to open

fast

86

1. curare blocks what receptors?
2. hexamethonium blocks what receptors

both nicotinic

87

muscarinic receptors are stimulated by:
AcH/nicotine/muscarine

AcH and muscarine
BUT NOT NICOTINE

88

muscarinic receptors are found at target organs when AcH is released by postganglionic neurons = all parasympathetic and some sympathetic (heart smooth muscle and glands). a _ EPSP is mediated

slow

89

atropine blocks which receptor

muscarinic = atropine
curare and hexamethonium = nicotinic

90

fibers that secrete AcH are called

cholinergic

91

fibers that secrete NE are called

adrenergic

92

the cholinergic effects at PRE GANGLIONIC neurons (both sympathetic and parasympathetic) are excitatory/inhibitory

excitatory

93

the cholinergic effects at PostGANGLIONIC parasympathetic) are excitatory/inhibitory

inhibitory OR excitatory

94

all preganglionic neurons are

cholinergic in both SNS and PNS

95

1. all or most of postganglionic neurons in PNS are
2. most of postganglionic neurons in SNS are
3. the exception is in postganglionic sympathetic nerve fibers to the sweat glands and piloerector muscles of the hairs are

1. cholinergic (Ach)
2. adrenergic (NE)
3. cholinergic

96

corticospinal tract is aka

pyramidal tract

97

corticospinal tract carries messages for

voluntary motor movement (fine skilled movements of skeletal muscle) to the lower motor neurons (LMN) in the brain stem and spinal cord.

98

corticospinal tract aka pyramidal tract is direct and monosynaptic = means

does not synapse with other cells until reaches final destination in brain stem or spinal cord. therefore very rapid transmission

99

fibers of the pyramidal tract that synapse with the cranial nerves located in the brain stem form the _ tract

coticobulbar tract = carries motor messages important for speech and swallowing

100

the fibers of the pyramidal tract that synapse with spinal nerves sending out messages to skeletal muscle for voluntary movement are called

corticospinal tract

101

The corticospinal tract DECUSSATE (85%) of the fibers at ___ to cross to opposite side of the brain.

lower medulla

102

The corticospinal tract DECUSSATE (85%) of the fibers.these fibers are called

the lateral corticospinal tract or the crossed pyramidal tract

103

corticospinal tract fibers that don't (10-15%) continue down ipsilaterally. they are called

uncrossed or direct fibers aka direct pyramidal tract. or the ventral pyramidal tract or the anterior corticospinal tract

104

descending pathways are subdivided into a LATERAL AND MEDIAL SYSTEM. the __ ends on motor neurons that go to the limb muscles and on lateral interneurons

lateral

105

descending pathways are subdivided into a LATERAL AND MEDIAL SYSTEM. the __ ends on medial interneurons

medial

106

the lateral descending system includes the lateral corticospinal tract that is part of the corticobulbar tract. these will effect ___ motor neurons and supply the muscle of the limbs, digits and muscles of the lower part of the face and tongue

contralateral

107

the _descending system includes the ventral corticospinal, lateral and medial vestibulospinal, reticulospinal and tectospinal tracts. these affect posture and provide motor background for movement of the limbs and digits

medial

108

preganglionic fibers always reside in the

cns

109

postganglionic fibers always lie in

peripheral ganglia

110

sympathetic/parasympathetic preganglionic neurons are located in the thoracolumbar region of the spinal cord

sympathetic

111

sympathetic/parasympathetic preganglionic neurons are located in the cranial nerve nuclei or the sacral spinal cord

parasympathetic

112

sympathetic/parasympathetic postganglionic neurons are located in the paravertebral and prevertrebral ganglia

sympathetic

113

sympathetic/parasympathetic postganglionic neurons are located in the ganglia in or near the target organ

parasympathetic

114

sympathetic preganglionic axons are __ while their postganglionic axons are __

(long or short)

short preganglionic
post ganglionic are long

115

parasympathetic preganglionic axons are __ while their postganglionic axons are __

(long or short)

long
short
(opposite of SNS)

116

the _ nervous system includes the myenteric and submucosal plexus in the wall of the GI tract.

enteric

117

the myenteric plexus regulates ___

motility

118

the submucosal plexus regulates

ion and water transport and secretion

119

preganglionic and postganglionic neurons release _NT that act on _ receptros

AcH
muscarinic

120

interneurons in ganglia release

catecholamines

121

sympathetic preganglionic neurons release _ and _ post ganglionic neurons

pre = AcH
post = NE

122

EXCEPTION: sympmathetic postganglionic neurons that supply sweat glands release

AcH

123

all __ganglionic neurons are cholinergic in both SNS and PNS = release AcH

pregagnlionic

124

Either all or almost all of the postganglionic neurons of the PNS are

cholinergic

125

most postganglionic sympathetic neurons are __ except for the ?

adrenergic
except for sweat glands and piloerector muscles of hairs which are cholinergic

126

two states of an ion channel Is high conductance = _
and zero conductance = _

open
closed

127

sodium channels rapidly open and close and K+ channels _ opening and closing

delay

128

hyperpolarization of the cell is a hypoexcitable state called the ___
this is happening as the potassium is leaving the interior of the cell making it more negative than the resting potential

RELATIVE refractory period = means in order to trigger a second action potential the depolarizing stimulus must be of a greater magnitude to achieve threshold.

129

during the absolute/relative refractory period the cell will not respond to any stimulus

absolute

130

presynaptic neurons transmit info __ a synapse

towards

131

post synaptic neurons transmit info _ from a synapse

away

132

nerve impulses only travel in one direction because?

synapses are polarized

133

electrical synapses are common in __ and rare in:

CNS/cardiac muscle/smooth muscle

common in cardiac and smooth muscle
rare in CNS.

134

electrical synapses are connected by _ junctions which allow the current to pass directly from postsynaptic neuron

gap

135

a Beta blocker used for hypertension has what mechanism?

blocks beta-1 adrenergic receptors in the heart causing a decrease in heart rate and force of contraction

136

beta blockers block the effects of

adrenaline on the body's beta receptors = slows nerve impulses that travel thru the heart so that it doesn't have to work as hard and needs less blood and O2. also block impulses that can cause arrhythmia

137

Selective beta blockers block which receptor more? 1 or 2?

beta 1 (heart)

138

B1 receptors are responsible for your

heart rate and strength of your heart beat

139

non selective beta blockers block

both B1 and B2 receptors.

140

B2 receptors are responsible for the function of your

smooth muscles

141

adrenergic receptors are located on autonomic effector organs that are regulated by

catecholamines
epinephrine and NE

142

two types of adrenergic receptors are

alpha and beta adrenergic receptors and Beta receptors (1 and 2)

143

alpha _ adrenergic receptors are located in sympathetic POSTSYNAPTIC nerve terminal = increase vascular smooth muscle contraction

alpha 1

144

alpha _ adrenergic receptors are located in sympathetic PRESYNAPTIC nerve terminals.

alpha 2

145

beta 1 adrenergic receptors are located in the

heart

146

beta 2 adrenergic receptors are located in the

liver and smooth muscle vasculature, bronchioles and uterus = increase hepatic glucose output, decrease contraction of BV's bronchioles and uterus

147

NE stimulates mainly which receptors

alpha

148

epinephrine stimulates_ receptors

alpha and beta receptors

149

beta cell of pancreas islets cells have which receptors (adrenergic)

alpha 2

150

when alpha 2 receptors are bound what happens

inhibits NE AND INSULIN release

151

T/F all cells including neurons have a resting potential that is about -70mV

true

152

T/F an action potential is propagated with the same shape and size along the entire length of the axon

true

153

resting potential is est because

there is more sodium ions outside of the cell than there are potassium inside. K+ and Na+ leakage thru potassium sodium leak channel. more potassium leaks out bc the channels are 100x more permeable to K+ than Na+. also due to Na+/K+ pu,p = electrogenic pu,p.

154

the size of the resting membrane potential varies but in excitable cells ranges bw

-40 and -85mV

155

what cells lack a STABLE resting membrane potential

visceral smooth muscle and cardiac pacemaker cells

156

the only mode of communication bw the CNS and effectors = aka Final Common pathway

motor neurons

157

exteroreceptors, interoreceptors, and proprioceptors are _

sensory recptors

158

interorecptors are

viscerorecptors

159

free nerve endings respond to (3)

itch, movement ,pain and temperature

160

nocireceptors are?

free nerve endings that detect painful stimuli

161

merkel disks and root hair plexus are

free nerve endings

162

proprioceptors are found in

joints, muscles and tendons

163

when scaling and root planning you use a firm finger rest for minutes at a time. which receptors are used in sensing this CONTINUOUS PRESSURE?
a. pacinian corpuscle
b. meissner's corpuscles
c. ruffini's corpuscles
d. Krause's corpuscles

ruffini's corpuscles = dermis of skin, exteroreceptors

activated by mechanical/thermal stimuli by sensation of crude and persistent touch, heat

164

which receptor used when you manipulate an instrument in your fingers
a. pacinian corpuscle
b. meissner's corpuscles
c. ruffini's corpuscles
d. Krause's corpuscles

pacinian corpuscle
dermis of skin, joint capsules
deep pressure
high frequency vibration and stretch

165

a sensory receptor that receives external stimuli

exteroreceptor

166

activated by light pressure; mechanical, low frequency vibration and discriminative touch

a. pacinian corpuscle
b. meissner's corpuscles
c. ruffini's corpuscles
d. Krause's corpuscles

Meissner's corpuscle

167

these receptors are found in mucous membranes and respond to mechanical and thermal stimuli such as touch, low freq vibration and cold
a. pacinian corpuscle
b. meissner's corpuscles
c. ruffini's corpuscles
d. Krause's corpuscles

Krause's corpuscle

168

these receptors are found in the skin and joint capsules and are activated by deep pressure and mechanical, high freq vibration and stretch

Pacinian corpuscle

169

these receptors feel crude and PERSISTENT touch and heat (thermal)
a. pacinian corpuscle
b. meissner's corpuscles
c. ruffini's corpuscles
d. Krause's corpuscles

Ruffini's corpuscle

170

the only two receptors that are activated by heat
a. pacinian corpuscle
b. meissner's corpuscles
c. ruffini's corpuscles
d. Krause's corpuscles

Krause's corpuscle = in mucous membrane
Ruffini's corpuscle (in skin and exterorecptors)

171

a. pacinian corpuscle
b. meissner's corpuscles
c. ruffini's corpuscles
d. Krause's corpuscles

these are all __

encapsulated nerve endings of touch and pressure receptors

172

nocireceptors, merkel disks, and root hair plexus are all

free nerve endings

173

when someone tickles you what receptor is activated

nociceptors = pain, temp, itch ,tickle, stretch

174

___ contains low threshold mechanoreceptors, thermoreceptors, and nocireceptors

skin

175

muscles joints and viscera contain _ receptors

mechanoreceptors and nociceptors

176

baroreceptors are found in the __ and sense_

carotid sinus and the aortic arch = stretch receptors that respond to change in blood pressure

177

1. The ________ is a small cluster of chemoreceptors located near the fork (bifurcation) of the carotid artery (which runs along both sides of the throat).

carotid body
detects changes in the composition of arterial blood flowing through it, mainly the partial pressure of oxygen, but also of carbon dioxide. Furthermore, it is also sensitive to changes in pH and temperature.

178

is the carotid body more sensitive to CO2 or O2 changes

While the central chemoreceptors in the brainstem are highly sensitive to CO2 the carotid body is a peripheral chemoreceptor that mainly provides afferent input to the respiratory center that is highly O2 dependent. However, the carotid body also senses increases in CO2 partial pressure and decreases in arterial pH, but to a lesser degree than for O2

179

___is a dilated area superior to the bifurcation of the common carotid at the level of the superior border of thyroid cartilage. It is sensitive to pressure changes in the arterial blood at this level.contains numerous baroreceptors which function as a "sampling area" for many homeostatic mechanisms for maintaining blood pressure.

carotid sinus

180

the primary functional unit of the parasympathetic and sympathetic nervous system is the:

one/two/three/four neuron motor pathway

two neuron
preganglionic neuron in the CNS and a postganglionic neuron whose cell body is located in one of the autonomic ganglia

181

_ nervous system includes all nerves that control the muscles and external sensory receptors (muscle fibers and gland cells are effectors)

somatic

182

_ nervous system = the organs/viscera of our body such as heart stomach intestines

autonomic

183

ANS divisions

autonomic and parasympathetic nervous system

184

the _ nervous system includes the myenteric and submucosal plexus in the wall of the GI

enteric

185

myenteric plexus regulates

motility (to remember just look at the M)

186

submucosal plexus regulates

ions and water transport and secretion

187

1.do motor neurons in the ANS reach their targets directly?
2. do motor neurons in the somatic nervous system reach their targets directly?

1. no. they connect to a 2nd motor neuron that will reach the target organ
2. yes

188

motor neurons of the somatic or ANS system cannot send inhibitory signals thru their motor neurons

somatic cannot
ANS can

189

Parasympathetic system: all preganglionic neurons are ___ and almost all or most postganglionic are

cholinergic

190

Sympathetic nervous system: all preganglionic neurons are _ and most postsympathetic neruons are _ except for

cholinergic
post: adrenergic except for the sympathetic fibers to the sweat glands, pilorector muscles = cholinergic

191

adrenergic fibers release

NE

192

cholinergic fibers release

AcH

193

__ preganglionic neurons branch extensively and synapse with numerous postganglionic neurons. it is this high ratio of postganglionic to preganglionic fibers that results in widespread effects thru the body

sympathetic

194

the presynaptic sympathetic nerve fibers originate in the ___ horns of the spinal cord segments: _

lateral
T1-L2

195

the presynaptic sympathetic nerve fibers exit the spinal cord in the _ roots and eventually enter the ventral primary __

ventral (bc they are motor)
rami

196

the presynaptic sympathetic nerve fibers exit the ventral primary rami via __ rami communications which carry the presynaptic sympathetic fibers to the sympathetic trunk

white

197

the main nerves of the PNS are the

vagus nerves.

198

vagus nerves of the PNS originate in the

medulla oblongata

199

each preganglionic parasympathetic neuron synapses with just a few postganglionic neurons located

near or in the effector organs muscles or glands

200

Horner's syndrome is a lack of

sympathetic tone. causes miosis. ptosis, anhydrosis on the affected side

201

excessive PNS activity carried by the vagus nerve can cause a __ with hypotension and possible syncope (passing out, is defined as a transient loss of consciousness and postural tone)

vasovagal episode

202

in dentistry excessive PNS activity can be seen as

orthostatic hypotension.

203

AcH is made from _ using enzyme _

acetyl-CoA and choline
choline acetyltransferase

204

the AP conducted along the motor nerve causes depolarization and

an influx of calcium, which causes AcH to be released into the synapse

205

Ach binds to _ receptors on the motor end plate

nicotinic

206

the stimulation of th each receptor results in the opening of

sodium channels and some potassium channels = influx of sodium and efflux of potassium = small net depolarization termed miniature end plate potentials (mEPP)

207

if enough miniature end plate potentials (mEPP) occur simultaneously their summation creates a

end plate potential EPP (not an action potential) = a current in muscle tissue that sparks an AP in the muscle fiber

208

AcH is broken down into

acetate and choline by acetylcholinesterase (AChE) on the motor end plate

209

if acetylcholinesterase is inhibited there will be a pronlongation of the

EPP end plate potential which can lead to tetanus

210

synaptic delay

AcH diffuses across cleft and binds receptor changing its ion permeability and potential. this time is the synaptic delay

211

electrical/chemical synaptic transmission directly connect the cytosol of 2 neurons and allow rapid bidirectional current flow bw the neurons, acting as low pass filters

electrical

212

electrical/chemical synaptic transmission involves the release of transmitter from presynaptic terminal, diffusion of the NT across the cleft and binding to receptor

chemical

213

_ junctions correlate electrical synapses

gap

214

gap junctions contain channels formed by hemichannels called

connexons.

215

connexons are formed by proteins called

connexins

216

the single most important tract concerned with skilled voluntary activity is the _

corticospinal tract

217

the spinal cord extends from the level of the foramen magnum of the skull to the

first lumbar vertebra

218

the 6 columns of white matter in the spinal cord that contains the ascending and descending tracts are called the

funiculi

219

most ascending fibers that convey sensory info that originate on the right side of the body will

cross over and reach the region of the left side of the brain

220

the decussation of the ascending tracts for sensory occurs in the

medulla oblangata

221

the two major descending tracts from the brain are the

corticospinal (pyramidal) tracts and the extrapyramidal tracts.

222

the corticospinal tracts carry voluntary motor stimuli from the cerebral cortex to motor neurons in the spinal cord. they are called the pyramidal tracts bc some of them

cross in the pyramids of the medulla

223

the other tracts such as vestibulospinal anterior corticospinal lateral and anterior reticulospinal etc come from a variety of locations in the brain and are group named

extra pyramidal tracts

224

extrapyramidal tracts are associated with

muscle tone and balance

225

Glut-_# mediates glucose transport into RBC's and thru the blood brain barrier

GLUT-1

226

Glut-_# provides glucose to the liver and pancreatic cells

GLUT-2

227

Glut-_# is in muscle and adipose tissue and regulated by insulin

GLUT-4

228

Glut-_# is the main transporter in neurons

GLUT-3

229

Glut-_# transports fructose in the intestine and testis

GLUT-5

230

1. glucose transport into RBC's and thru the blood brain barrier
2. provides glucose to the liver and pancreatic cells
3. transporter in neurons
4. muscle and adipose tissue and regulated by insulin
5. transports fructose in the intestine and testis

1. GLUT-1
2. GLUT-2
3. GLUT-3
4. GLUT-4
5. GLUT-5

231

the classification and naming of stereoisomers are based on the

absolute configuration of the 4 substituents of the asymmetric carbon

232

what is the compound that is used for reference? it is the smallest sugar to have an asymmetric carbon

glyceraldehyde

233

the naming of configurations of both _ and _ is based on the absolute configuration of glyceraldehyde as established by x-ray diffraction

amino acids and simple sugars

234

L- amino acid stands for

levortatory

235

D- Amino acid stands for

dextrorotatory = the way they rotate light

236

D- amino acid, although not common are found in some _ and _

anitibiotics and bacterial cell walls

237

which patient has the least chance of edema formation:
one with inflammation
one who is standing
with venous constriction
with arteriolar constriction

arteriolar constriction
bc causes decreased capillary hydrostatic pressure.
note arteriolar dilation increases likelihood of edema.

238

the physical cause of edema is __ pressure in the interstitial places

positive.

under normal conditions, negative pressure is in the interstitium

239

systemic or generalized edema may be due to

heart failure or renal disease

240

massive systemic edema is called

anasarca

241

a 0.9% solution of sodium chloride or a 5% glucose solution are both hypertonic/isotonic to plasma

isotonic.

242

solution of sodium chloride greater than 0.9% is

hypertonic to plasma

243

solution of sodium chloride less than 0.9% is

hypotonic to plasma

244

in an isotonic solution the water potential on each side of the membrane is

the same

245

in an isotonic solution is there water movement

yes but the water that moves in one direction will be balanced by the amount that moves back in the other. There is no NET osmotic movement of water

246

which is not an oncogene:
HER-2/neu
ras
src
myc
CAAT

CAAT = this is the binding site for RNA transcription factors

247

__ is a defective gene that is involved in triggering cancer cell growth

oncogene

248

are proto-oncogenes normal or defective

= normal gene that can become an oncogene due to mutations or increased expression. The resultant protein may be termed as oncoprotein. in cancer cells proto oncogenes are mutated and create oncogenes

249

__ code for proteins that help to regulate cell growth and differentiation. they are often involved in signal transduction and execution of mitogenic signals, usually through their protein products

Proto-oncogenes

250

one or more _ are mutant in all forms of cancer

oncogenes

251

a proto oncogene is a gene that has functions to promote

cell division

252

when proto oncogenes are mutated, defective versions of these genes are formed (oncogenes) they may produce products that promote abnormal cell division. a key feature of oncogene activity is

a single altered allele leads to unregulated growth

253

in tumor suppressor genes __alleles must be defective to lead to abnormal cell division

both
(opposite of oncogenes which appears as only one altered allele)

254

What cancer is associated with the oncogene:
HER-2/neu: a growth factor receptor

30% of human breast cancer

255

What cancer is associated with the oncogene: ras: a signal transduction molecule

many different cancers of different origins including pancreas (90%), colon (50%), lung (30%), thyroid (50%), bladder 6%, ovarian 15%, breast skin liver kidney and some leukemias

256

What cancer is associated with the oncogene: myc: a transcription factor

Burkitt's lymphoma,
B cell leukemia and lung cancer

257

What cancer is associated with the oncogene: src: a protein tyrosine kinase

the first oncogene ever discovered
neuroblastoma
small cell lung cancer
colon and breast carcinomas
rhabdomyosarcoma

258

osteoblasts make a protein mixture called __ which mineralizes to become bone. it is primarily composed of

osteoid
type 1 collagen

259

the intracellular matrix of bone contains a calcium binding protein called __ and a calcium and collagen binding protein called

osteocalcin
osteonectin

260

bone density and structural integrity decrease after age _ in men and _ in women

45 men
30 women

261

the pitch of a sound is related mainly to the amplitude or the frequency of the sound wave

frequency

262

a sound can be characterized according to its pitch, loudness, and timbre. what is timbre

quality

263

the higher the frequency, the __ the pitch

higher

264

frequency is measured in

Hz or cycles per second

265

the __ of a sound is related to the intensity and the amplitude of the wave

loudness

266

the greater the amplitude of a sound, the __ the intensity of the wave and the louder the sound

greater

267

intensity is measured in

decibels (dB)

268

__ is measured in Hz and __ is measured in decibels (dB)

frequency
intensity

269

the __ of a sound is related to the presence of additional sound-wave frequencies superimposed on the principal frequency

timbre (sound quality)

270

intracellular fluid (ICF) or extracellular fluid (ECF) compromises 2/3 of the body's WATER

ICF

271

intracellular fluid (ICF) or extracellular fluid (ECF) compromises 1/3 of the body's WATER

ECF (Outside of the cell)

272

is the ICF homogenous in the body

no

273

the ICF is made mostly of a solution of

POTASSIUM and organic ions, proteins, etc

274

the ECF is made up of primarily

NaCl and NaHCO3 solution

275

the __ is further subdivided into 3 subcompartments: plasma, transcellular fluid, and interstitial fluid

ECF

276

interstitial fluid surrounds the cells but does not circulate. it comprises about __ of the ECF

75%

277

plasma circulates as the extracellular component of blood. it makes up _ % of the ECF

25%

278

___ is a set of fluids outside of normal compartments. 1-2 L of fluid that makes up the CSF, digestive juices, mucous etc

transcellular fluid

279

60-40-20 rule?

60% of body weight is water
40% of body weight is ICF
20%of body weight is ECF

280

sweating begins at what temp

37degrees celsius and up (98.6F)

281

human body regulates its core temp bw

98F and 100F

282

osmolarity vs tonicity: osmolarity compares the amount of solutes in 2 solutions while tonicity compares the

osmotic pressure gradient

283

tonicity measures _ solutes

impermeable.

284

osmolarity measures _ solutes

all solutes in solution

285

heat flows form hot to cold or cold to hot

hot to cold

286

Isotopes of an element have different ___ but same ___

different weights (bc different number of neurons)
same chemical properties

287

isotopes are stable or radioactive forms of an element that differ in atomic weight but are otherwise chemically identical to the ___ form of the element

naturally abundant form

288

isotopes have the same

protons/atomic number

289

isotopes have different

mass numbers/number of neutrons

290

the radioactive forms of isotopes are used as _ in medical radiography

tracers

291

the cell cycle stages are

G1-S-G2-M

292

the G1 stage stands for

GAP1

293

the S stage stands for

synthesis (the stage when DNA replication occurs)

294

the G2 stage stands for

GAP2

295

The M stage stands for

mitosis

296

mitosis is divided inot

PMAT = prophase, prmetaphase, metaphase, anaphase, and telophase

297

interphase is when?

G1, S and G2 (before mitosis)

298

growth and preparation of the chromosome occurs in what stage

G1

299

in what stage do we prepare for mitosis

G2

300

protein and RNA synthesis occur in all phases of the cell cycle except the

M phase (mitosis)

301

a eukaryotic cell cant divide into 2 or more unless what 2 process occur

doubling of the genome (DNA) in S phase and halving of that genome during mitosis

302

first antibody to appear in the circulation after antigen stimulation

IgM

303

the most common antibody in our body is

IgG

304

the second antibody to appear in circulation after antigen stimulation

IgG

305

which antibody can pass the placenta and enter the fetal circulation

IgG

306

second most abundant antibody

IgA

307

which antibody has a function that is unknown

IgD

308

what antibody acts as a receptor on the surface of B lymphocytes

IgD

309

which antibody is LARGE and has 5 antibody units

IgM

310

which antibody is important in complement activation

IgM

311

which antibody is the primary antibody against A and B antigens on RBCs

IgM

312

which antibody is present in only trace amounts in the serum

Ige