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Flashcards in Msk Final Deck (289):
1

Autoimmune disorder attaching schwann cells causing demyelination in the peripheral nervous system

Guillian barre

2

hypaxial/ Extrinsic back muscles are innervated by who

CN11 and brachial plexus branches

3

epaxial/ intrinsic back muscles are innervated by who

dorsal rami of spinal nerves

4

what muscles make up the erector spinae group of intrinsic back muscles? They extend and laterally flex vertebral column.

spinalis, longissimus, iliocostalis

5

what muscles make up the transversospinalis group of intrinsic back muslces

rotatores, multifidus, semispinalis

6

what modalities are carried by dorsal root fibers

sensory

7

what modalities are carried by dorsal ramus of spinal nerve

sensory and motor

8

what modalities are carried by ventral root fibers

motor

9

what modalities are carried by ventral ramus of spinal nerve

sensory and motor

10

insertion, action, and innervation of splenius cervicis (originates at nuchal ligament)

transverse process of C-3
extend head/ neck, lateral flexion and rotation of neck
dorsal rami of spinal nerves

11

insertion, action, and innervation of splenius capitis

lateral part of mastoid process
extend head/ neck, lateral flexion and rotation of neck
dorsal rami of spinal nerves

12

action, blood supply, and innervation of iliocostalis (runs from iliac crest to lumbar, thoracic, and cervical transverse processes)

extend and laterally flex vertebral column
posterior intercostal and lumbar aa.
dorsal rami of spinal nerves

13

action, blood supply, and innervation of longissimus

extend/ lateral flex vertebral column
posterior intercostal aa. for thoracis and cervicis portions
occipital a. for capitis portion
nerve: dorsal rami

14

action, blood supply, and innervation of spinalis m. (thoracis, cervicis, capitis portions)

extend and lateral flex vertebral column
posterior intercostal aa.
dorsal rami

15

blood supply and innervation for semispinalis

cervicis and capitis: deep cervical a.
thoracis: posterior intercostal aa.
all are innervated by dorsal rami

16

muscle running from transverse process of one vertebra to spinous process of the vertebra superiorly

multifidus (attach to tip of spinous process)
rotatores (2 bellies attach at base of spinous process)

17

blood supply, innervation, and action of multifidus

posterior lumbar arteries
dorsal rami
stabilize vertebra during localized movement

18

blood supply, innervation, and action of rotatores

posterior intercostal arteries
dorsal rami
extend head and spine and rotate contralaterally

19

what is the only intrinsic back muscle that receives BOTH ventral and dorsal contribution from spinal nerves

intertransversari m.

20

blood supply to interspinales

vertebra, occipital, posterior intercostal aa.

21

blood supply to intertransversari

deep cervical, vertebral, posterior intercostal aa.

22

blood supply to legator costarum

posterior intercostal a.

23

which ligament surrounds the dens holding it in place

transverse ligament of the atlas

24

ligament holding atlas and axis together posteriorly

deep: cruciate ligament
superficial: tectorial membrane

25

the mm. of the sub occipital region are all innervated by dorsal rami of which spinal nerve?

C1: sub occipital nerve

26

rectus capitis posterior major and minor, obliquus capitis superior and inferior are postural muscles that aid extension and rotation at which joint

atlantoaxial joint (they are sub occipital muslces)

27

what are the borders and contents of sub occipital triangle

boarders: obliquus capités superior and inferior and rectus capitis major
contents: suboccipital n. and vertebral a.

28

which vertebrae have foramina in their transverse process

cervical

29

which vertebrae have bifid spinous process

cervical

30

which vertebrae have facets for ribs

thoracic

31

which vertebrae have greatest ROM

cervical

32

which vertebrae have greatest strain

lumbar (dispace energy to pelvis)

33

where does ligamentum flavum run

just anteriorly to the spinous process of vertebra

34

what structure surrounds nucleus pulpous to help maintain intervertebral joints

annulus fibrosus

35

what supplies blood to the vertebra

cervical- vertebral/ cervical aa
thoracic- posterior intercostal as
lumbar- subcostal and lumbar aa
sacral- iliolumbar/ sacral aa

36

what are the 2 enlargements of the spinal cord

cervical, lumbar

37

what is the outermost meningeal covering of the spinal cord

dura mater

38

which layer of spinal cord meningeal covering contains circulating CSF

arachnoid mater (middle layer)

39

what is the innermost layer of meningeal covering for the spinal cord and what connects it to the spinal cord

pia mater
denticulate ligaments

40

spinal nerve roots are partially covered by which meningeal layer

dura mater

41

which ribs are considered false ribs since they articulate with the sternum via cartilage rather than bone

8-10

42

which ribs are considered floating since they do not have their own cartilaginous or bony attachment to the sternum

11 and 12

43

what are the 3 components of the sternum

manubrium, body, xiphoid

44

which rib inserts to the xiphosternal joint?

7th

45

which rib inserts to the manubrosternal joint

2

46

mammary glands are classified as what

modified sweat glands

47

the breast rests on what superficial structure

pectoral fascia

48

name the potential space between breast and pectoral fascia

retromammary space

49

breast is innervated by what

intercostal nn 4-6

50

mammary gland lobules condense and drain into what structure before converging on the nipple

lactiferous ducts then sinuses

51

mammary gland lobules are separated by what named structure that also attaches to dermis of overlaying skin

suspensory ligament (Cooper's ligament)

52

arterial supply to breast tissue comes from where

axillary a. (via mammary branches)
internal thoracic a.

53

what causes rapid metastasis of breast cancer

lots of lymph drainage to axillary nodes

54

lymph from nipple, aerola, and lactiferous lobules drains to what

subareolar lymph nodes

55

75% of breast lymph drains to what

axillary nodes (pectoral, central, apical)

56

what innervates breast tissue

supraclavicular nn.
intercostal nn 4-6 (mammary branches)

57

deltopectoral (clavipectoral) triangle borders

deltoid, pec major, middle 1/3 of clavicle

58

deltopectoral (clavipectoral) triangle contents

cephalic vein
deltopectoral lymph nodes
deltoid branch of thoracoacromial a. (from axillary a)

59

what kind of fascia encloses the pec major

pectoral fascia

60

what kind of fascia encloses the subclavius and pec minor

clavipectoral fascia

61

contents of clavipectoral triangle pierce which layer of fascia

clavipectoral fascia

62

the clavipectoral fascia becomes what inferior to the pec minor

suspensory ligament of the axilla

63

innervation and blood supply to pec major

pectoral branch of thoracoacromial arterial trunk
lateral and medial pectoral nn. (C5-T1)

64

innervation and blood supply to pec minor

pectoral branch of thoracoacromial arterial trunk
medial pectoral n (C8-T1)... this also pierces the muscle

65

innervation and blood supply to subclavius

clavicular branches of thoracoacromial trunk
nerve to subclavius (C5-6)

66

innervation and blood supply to serratus anterior

lateral thoracic a
long thoracic n. (C5,6,7)

67

peau d'orange (skin resembling orange peel) of the breast indicates what

blockage of cutaneous lymph vessels

68

breast elevates when woman places hands on hips and lesses elbows foreword indicates what is happening

invasion of pec major by the cancer

69

finger sized dimple in superiolateral quadrant of breast indicates what condition

shortening of suspensory ligaments by cancer in axillary tail of breast

70

action of pec major

adduct, medial rotate, flex, extend humerus

anterior and inferior movement of scapula

71

action of pec minor

stabilize scapula

72

action of subclavius

depress and anchor scapula

73

action of serratus anterior

protraction and upward rotation of scapula

74

thoracoacromial trunk of axillary artery has what branches

acromial, deltoid, pectoral

75

what muscle is responsible for splitting the axillary artery into its 3 major regions in the clavipectoral region

pec minor

76

what major branch is given off of the axillary artery in part 1 (proximal to p minor)

superior thoracic a

77

what major branch is given off of the axillary artery in part 2 (posterior to p minor)

thoracoacromial trunk

78

what major branch is given off of the axillary artery in part 3 (distal to p minor)

subscapular a (circumflex scapular and thoracodorsal branches)
anterior circumflex humeral
posterior circumflex humoral

79

what are the anastomosing arterial branches of the scapula

suprascapular, dorsal scapular, posterior intercostal aa, circumflex scapular, thoracodorsal a

80

what are the 2 superficial venous contributions to axillary vein in the pectoral region

cephalic v
basilic v

81

what are the boundaries of axilla

anterior: pec major and minor
posterior: scapula and subscapularis
lateral: humerus (intertubercular sulcus and biceps tendon)

82

what all is contained in the axillary sheath

axillary v
axillary a
brachial plexus

83

shoulder joints are held together by which ligaments

coracoclavicular (trapezoid and conoid)
coracoacromial
glenohumeral (superior, middle, inferior)

84

what are the rotator cuff muscles of the shoulder

subscapularis
supraspinatus
infraspinatus
teres minor

85

long thoracic n (C5, 6, 7) innervates which muscle

serratus anterior

86

blood supply and innervation to deltoid

deltoid branch of thoracoacromial arterial trunk
axillary n

87

blood supply and innervation to trees major

circumflex scapular a
lower sub scapular n

88

the transverse ligament of the humerus wraps around what holding it in the inter tubercular groove of the humerus

biceps tendon

89

what articulates with the greater tubercle of the humerus

supraspinatus, infraspinatus, teres minor

90

what articulates with the lesser tubercle of the humerus

subscapularis

91

blood supply and innervation to supraspinatus

suprascapular a
suprascapular n

92

blood supply and innervation to subscapularis

subscapular a
upper and lower subscapular nn

93

largest and strongest rotator cuff muscle

subscapularis

94

injuries to which rotator cuff muscle can lead to occipital tendon instability and biceps tendonitis

subscapularis

95

blood supply and innervation to infraspinatus

suprascapular a
suprascapular n (C5-6)

96

blood supply and innervation to trees minor

circumflex scapular a
axillary n

97

what arterial branches come from the subclavian artery medial to the anterior scalene m

internal thoracic a
vertebral a
thyrocervical arterial trunk

98

what are the 4 branches of the thyrocervical arterial trunk

transverse cervical a
inferior thyroid a
ascending cervical a
suprascapular a

99

what arterial branches come from the subclavian artery posterior to the anterior scalene m

costocervical arterial trunk (supreme intercostal and deep cervical artery)

100

this special artery can arise from subclavian artery or from the transverse cervical artery (30% of the time)

dorsal scapular a (always runs along vertebral border of scapula

101

the most superficial "space" of the posterior shoulder

triangle of auscultation

102

trees major, trees minor, and the long and lateral heads of triceps brachii all converge at the posterior shoulder to make what 3 spaces

triangular space (circumflex scapular a)
quadrangular space (axillary n, post circumflex humeral a)
triangular interval (deep brachial a, radial n)

103

first long bone to completely ossify (can present as congenital pseudoarthrosis or poorly healed fracture if ossification fails)

clavicle

104

what muscles abduct humerus

deltoid
supraspinatus

105

what muscles adduct humerus

teres major

106

what muscles flex humerus

deltoid

107

what muscles extend humerus

deltoid

108

what muscles lateral rotate humerus

infraspinatus, teres minor, deltoid

109

what muscles medial rotate humerus

trees major, subscapularis, deltoid

110

what muscles protract scapula

serratus anterior

111

what muscles depress scapula

serratus anterior

112

what muscles upward rotate scapula

serratus anterior

113

impingement syndrome in the shoulder can involve what two structures

subacromial bursitis
supraspintaus tendonitis

114

which tendon likely tears in a "rotator cuff tear"

supraspinatus tendon

115

size of quadrangular space is reduced compressing what structure

axillary n (or posterior circumflex humeral artery)

116

what nerve supplies the skin over the forearm

lateral and medial antebrachial cutaneous n

117

the main arterial supply for the superficial palmar arch comes from what a

ulnar a

118

the main arterial supply for the deep palmar arch comes from what a

radial a

119

superficial muscles of the forearm (lateral to medial)

pronator teres
flexor carpi radialis
palmaris longus
flexor carpi ulnaris

120

intermediate (layer 2) muscles of the forearm (lateral to medial)

flexor digitorum superficialis

121

deep muscles of the forearm (lateral to medial)

flexor pollicis longus, flexor digitorum profundus, pronator quadratus

122

blood supply and innervation for pronator teres

anterior ulnar recurrent a
median n

123

blood supply and innervation for flexor carpi radialis

ulnar a
median n

124

blood supply and innervation for palmaris longus

ulnar a
median n

125

blood supply and innervation for flexor carpi ulnaris

ulnar a
ulnar n

126

blood supply and innervation for flexor digitorum superficialis

ulnar a
median n

127

blood supply and innervation for flexor digitorum profundus

anterior interosseous a
median and ulnar nn

128

blood supply and innervation for flexor pollicis longus

anterior interosseous a
median n via anterior interosseous n

129

blood supply and innervation for pronator quadratus

anterior interosseous a
median n via anterior interosseous n

130

which nerve runs just superficial to the medial epicondyle of the humerus before supplying intrinsic hand mm

ulnar nerve

131

the median n pierces which forearm m

pronator teres

132

which nerve runs through the carpal tunnel making it susceptible to compression during carpal tunnel syndrome

median n

133

the anterior interosseous n and a run just deep to what muscle

pronator quadratus

134

What cutaneous innervations of the dorsum of the hand contain?

Ulnar nerve- lateral 2.5 fingers and lateral metatarsals/carpals

Radial nerve- thumb, index, and half. Of middle finger and skin proximal to those fingers

Median nerve- index and middle fingers distal to PIP joint

135

What muscles make up the radialis group

Brachioradialis
Extensor carpi radialis longus
Extensor carpi radialis brevis

136

Which muscles make up the superficial layer of the posterior forearm

extensor carpi ulnaris
Extensor digiti minimi
Extensor digitorum

137

Which muscles make up the deep layer of the posterior forearm

Extensor indicus
Extensor pollicis longus
Extensor pollicis brevis
Adductor pollicis longus
Supinator

138

What is the common extensor origin of the forearm

Lateral epicondyle of humerus

139

All muscles of the posterior forearm are innervated by who

Radial nerve (deep branch or posterior interosseous n)

140

Superficial branch of the radial nerve does what

Cutaneous innervation in lateral hand

141

Blood supply and innervation to brachioradialis

Radial collateral and recurrent radial aa
Radial n

142

What is the action of brachioradialis

Flex forearm when pronated

143

Blood supply and innervation to extensor carpi radialis longus

Radial collateral, radial recurrent, radial interosseous aa
Radial n

144

Blood supply and innervation to extensor carpi radialis brevis

Radial collateral, radial recurrent, recurrent interosseous aa
Deep branch of radial n

145

Blood supply and innervation to extensor digitorum

Posterior interosseous, recurrent interosseous, perforating branches aa

Posterior interosseous n

146

Blood supply and innervation to extensor digiti minimi

Posterior interosseous, recurrent interosseous, perforating branches aa

Posterior interosseous n

147

When extensor digitorum contracts it. Pulls what structure causing IP joints to extend?

Extensor expansion (extensor hood mechanism)

148

Blood supply and innervation to extensor carpi ulnaris

Radial collateral, radial recurrent, recurrent interosseous aa
Posterior interosseous n

149

Blood supply and innervation to supinator

Radial, posterior interosseous, radial recurrent aa


Deep branch of radial n

150

Blood supply and innervation to extensor indicus

Posterior interosseous and perforating branch aa
Posterior interosseous n

151

Blood supply and innervation to adductor pollicis longus

Posterior interosseous a
Posterior interosseous n

152

Blood supply and innervation to extensor pollicis brevis

Posterior interosseous and perforating branch aa
Posterior interosseous n

153

Blood supply and innervation to extensor pollicis longus

Posterior interosseous a
Posterior interosseous n

154

What is the anastomosis in the hand

Radial artery contributes to both deep palmar arch and dorsal carpal arch

155

The deep branch of the radial nerve continues as the posterior interosseous nerve. After passing through what structure

Supinator m

156

Which artery and bone lie deep to the anatomical snuff box

Radial a
Scaphoid bone

157

Which structures are ruptured in a shoulder separation but not a shoulder dislocation

Acromioclavicular ligament (and sometimes other shoulder ligaments as well)

158

What nerve is most commonly injured with shoulder dislocation

Axillary n

159

When do upper limbs form? Lower limbs?

Day 26- arms
Day 27/28- Legs

160

What layer gives rise to limbs

Somatic layer of lateral plate mesoderm

161

Mesenchyme thickens at the surface to direct limb bud formation at what named structure

Apical ectodermal ridge

162

What signal causes mesenchyme to migrate and proliferate?

FGF8

163

What genes direct limb bud formation proximal to distal? What takes over as they get farther from the axial skeleton?

HOX genes until

RA takes over (tells mesenchyme which bones to form from proximal)

FGF8 signals at distal end

164

First cells to be exposed to RA become humerus and femur and are called what

Stylopod

165

cells that when exposed to RA become radius/ulna or tibia/fibula and are called what

Zeugopod

166

Last cells to be exposed to RA become carpels, metacarpals, tarsals, metatarsals, digits and are called what

Autopod

167

When do hand and foot plates appear along with chondrification centers appear in developing embryo?

Week 5

168

When do digital rays of hands appear in developing embryo? (Entire limb skeleton is cartilage)

Week 6

169

What occurs that removes webbing between our digits? When does this occur in developing embryo?

Apoptosis
Week 8

170

When do digital rays of feet form in developing embryo (and osteogenesis of long bones begins along with limb rotation)

Week 7

171

Limb musculature is derived from what

Dorsolateral cells of somites

172

During week 7, upper limbs rotate 90 degrees in which direction

Lateral rotation

173

During week 7, lower limbs rotate 90 degrees in which direction

Medial rotation

174

Cranial surface (preaxial/anterior) surface of the upper limb includes what features

Thumb and radius

175

Caudal surface (postaxial/posterior) surface of the upper limb includes what features

Ulna and little finger

176

Motor axons from spinal cord enter limb buds when during development

Week 5

177

What generates first motor or sensory axons?

Motor

178

Neural crest cells are doing what with the PNS during week 5 of development

Making sensory axons and schwann cells (myelination)

179

In the developing embryo what is the main blood. Supply. To the lower limb (before it gets taken over. By femoral a)

Deep femoral a (profunda femoris a)

180

Most common musculoskeletal defect: sole of foot turned medially and foot is inverted (more common in males) fixed usually by casting

Club foot

181

Musculoskeletal defect occurs more in females and involves under development of acetabulum of hip bone and joint laxity

Developmental hip dysplasia

182

Patterning and positioning of limbs along craniocaudal axis is regulated by what genes

HOX (also control type and shape of the bones in limbs)

183

Proximodistal growth and patterning of limbs occurs at what area and requires what type of signalling

Apical ectodermal ridge, FGF signalling

184

Dorso-ventral patterning helps us form flexor and extensor surfaces of limbs. The ventral surface is maintained by ___ signaling and dorsal is maintained by ___ signaling. These signals set up the apical ectodermal ridge

BMPS (ventral)
Wnt7 (dorsal)

185

Anterior posterior patterning of the limb is controlled by establishing what zone on posterior side of limb? What signal signals this posterior region?

Zone of polarizing activity
Shh and RA

186

Loss of ZPA (zone of polarizing activity) results in what

Loss of posterior elements (digits 3-5 or ulna) and you WILL have a thumb

187

Upregulation of ZPA (zone of polarizing activity) results in what

Polydactyly (extra digits) and you WILL have a thumb

188

Duplication of ZPA (zone of polarizing activity) results in what

Polydactyly::: Duplication of posterior elements (digits 3-5 mirrored on both sides of the "thumb" but may not have fingers with only 2 phalanges)

189

Which elements form first: posterior (little finger/ ulna) or anterior elements (thumb/ radius)

Posterior forms first!
(Thus disruption of anteroposterior patterning= loss of anterior elements)

190

Congenital joint contractures of 1 or more joints possibly caused by neurologic defect, muscular abnormalities, fetal crowding

Arthrogryposis

191

Vascuature remodeling occurs in the forearm and most people lose this artery but it canremain in some people

Median a

192

Abnormal short digits due to week 6 malfunction

Bradydactyly

193

Fusion of digits because apoptosis fails in week 8

Syndactyly

194

Development of limbs close to the body is called __ and can occur after mama bear takes what med?

Phocomelia , Thalidomide

195

MOA for phocomelia

FGF does not signal AER correctly causing the short limbs

196

Absence of limbs

Amelia (wk 4 upper limbs, wk 5 lower)

197

Absence of part of limb and the two sub types

Meromelia (hemimelia is missing a bone like ulna, phocomelia is limb develop close to body)

198

Which stage of limb development is most affected in hemimelia

Zeugopod

199

what are the steps involved in neurotransmission at the neuromuscular junction

ACh synthesis, storage, release, destruction leads to muscle contraction

200

enzyme that combines acetyl coA and choline to form ACh

choline acetyltransferase (ChAT)

201

alzheimer patients have reduced cerebral production of what ACh forming enzyme?

ChAT

202

by what mechanism is ACh shuttled into storage vesicles after synthesis

ACh vesicular transporter + ATP

203

upon depolarization, what kind of voltage gated channels open?

Ca++ channels open and calcium flows in

204

what is the role of calcium in NMJ transmission

promotes vesicle fusion to the presynaptic membrane

205

what are the vesicular and plasma membrane proteins that initiate vesicle plasma membrane fusion to release ACh

VAMP and SNAP (they are SNAREs)

206

what is known to block the snare complex thus inhibiting release of ACh from the presynaptic neuron

botulinum toxin (BOTOX)

207

enzyme that cleaves ACh into cholineand acetate so that choline can go back to motor neuron for reuse

acetylcholinesterase

208

sodium potassium pumps in the presynaptic membrane of the NMJ create a sodium gradient that is used to bring what into the cell for recycling in making neurotransmitter

choline

209

what is the effect of an acetylcholinesterase inhibitors

increase ACh

210

what type of ACh receptor do you find in skeletal muscle

nicotinic

211

where do we often find muscarinic ACh-R's

smooth muscle mostly but also cardiac muscle

212

what type of channel is a nicotinic ACh-R?

ligand gated na+ channel

213

what type of channel is a muscarinic ACh-R?

GPCR

214

what lines the pore of the nicotinic ACh-R?

negatively charged AA side chains (Asp, Glu)

215

what are the 3 types of nAChRs?

skeletal, peripheral neuronal, central neuronal

216

what agonists bind to muscular nicotinic ACh receptors

nicotine
ACh
succinyl choline

217

what antagonists bind to muscular nicotinic ACh receptors

atracurium
vecuronium
d-tubocurarine
pancuronium

218

how can drugs target only one subtype of nicotinic ACh receptors

each subtype is made up of different subunits and these are the target for drugs that allow us to target only one subtype

219

how many molecules of ACh have to bind in order to activate a nAChR and allow Na+, K+ or Ca++ to pass through down their concentration gradient

2

220

while the motor end plate cannot perform this action itself, if enough Na+ comes in the adjacent muscle membrane can do what

depolarize (gotta reach threshold)

221

the presence of an action potential in the neuron at the NMJ causes the opening of what type of channel

voltage gated Ca++ (the calcium helps with vesicle fusion)

222

Tetrodotoxin (puffer fish) can cause weakness, dizzy, paresthesia, reflex loss, hypotension, paralysis by what MOA?

inhibiting voltage gated Na+ channels thus blocking axonal conduction

223

Local anesthetics like lidocaine, bupivacaine, procaine are used to control pain during procedures by what MOA?

inhibiting Na+ channels to inhibit axonal conduction
(especially sensory neurons)

224

batrachotoxin (poison dart frog) is potent and causes paralysis by what MOA?

increased Na+ permeability (persistent depolarization)

225

Botulinum toxin causes flaccid paralysis by what MOA

cleave SNARE components so neuron cannot release ACh

226

tetanus toxin causes muscle spasms and rigid paralysis by what MOA

cleave SNARE components to block vesicle fusion and travel up the spinal cord (retrograde movement)

227

curare alkaloids (like d-tubocurarine) are used during anesthesia to relax muscles (flaccid paralysis) by inhibiting Ach binding to receptor. whats the MOA

compete with Ach for the receptor

228

this Ach agonist is used as an induction agent for anesthesia and acts by binding nAChRs causing first depolarization which continues until receptor blockade and paralysis

succinylcholine

229

which of the Ach agonists is a depolarizing blocker?
which of the Ach agonists is a nondepolarizing blocker?

succinylcholine
Curare alkaloids (non)

230

whats the function of cholinesterase inhibitors and when do we use them?

they increase ACh at the NMJ
parkinson, alzheimer, myasthenia gravis, nerve gas, reverse neuromuscular blockade during anesthesia

231

what drug inhibits ryanodine receptors in SR blocking release of ca++? when do we use it?

dantrolene
malignant hypothermia, upper motor nerve disorders

232

Property of muscles : Capacity to respond to stimulus

Excitability

233

Property of muscles : ability to shorten and generate pulling force

Contratility

234

Property of muscles : can strech back to original length

Extensibility

235

Property of muscles : can recoil to original resting length after stretched

Elasticity

236

Muscle fibers are surrounded by what structures that deliver oxygen and nutrients

Capillary beds

237

Each skeletal muscle Fiber contains several nuclei. As well as what to maintain energy required for contraction

Lots of mitochondria, myoglobin

238

How and when does the troponin-tropomyosin complex move to expose actins myosin binding site?

When calcium binds to troponin C, it causes the troponin-tropomyosin complex to release from the myosin binding site

239

Which myofilament has ATPase activity

Myosin (thick filament)

240

If the. Power stroke. Generated by actin/myosin interaction is strong enough to move the load what type of muscle contraction results?

Isotonic (muscle shortens)

241

If the. Power stroke. Generated by actin/myosin interaction is NOT strong enough to move the load what type of muscle contraction results?

Isometric (no shortening of muscle)

242

What type of Ach receptors. Do you. Find at the. Neuromuscular junction

Nicotinic

243

Where. Does an action potential propagate to in a muscle cell

Through sarcolemma and down t tubules

244

Voltage gated ca++ channels allow calcium out of the sarcoplasmic Reticulum and open in response to binding of what molecules

Ryanodine, DHPP

245

Renal failure, blood. Clotting, and cardiac arrhythmias can result from leakage of ca++, K+, phosphate, urate, myoglobin, or lactate dehydrogenase into circulation as a result of what condition

Rhabdomyolysis (unaccustomed physical excersize)

246

When bound to actin, myosin heads pull causing sarcomere to shorten. What "bands disappear" as the thin filament moves toward the center

H and I

247

Which "band" in the sarcomere remains the same length during contraction

A band (myosin)

248

During contraction myosin forms a bond with an actin molecule. What do we call this bond

Crossbridge

249

Once a cross bridge is formed, myosin head bends and pulls itself along the actin filament. What is this motion called

Power stroke

250

What happens when ATP binds to myosin during power stroke

It releases from the actin

251

How do we. Restore calcium. Levels. After contraction

Active transport in the SR

252

After you die the cytosolic concentration of calcium rises because the muscle membrane is no longer active. calcium leaks out and moves troponin complex aside letting actin and myosin form cross bridges. Since no ATP is being generated, they cannot detach so dead muscles remain stiff. What do we call this?

Rigor Mortis

253

What mechanisms control strength of a muscle contraction

1. Motor unit recruitment
2. Individual fiber contractility manipulation (frequency of stimulation)

254

What makes up a motor unit

1 neuron + all muscle fibers it supplies

255

What happens if two action potentials reach one muscle fiber at the same time

Summation - tension of the two is added (more time is needed for ca++ to leave after and muscle to relax)

256

What do you call it when repeated stimulation to muscle results in a plateau of tension and the muscle stays there

Tetanus

257

A decline in muscles ability to maintain a constant force of crontraction in the face of long term repetitive stimulation

Fatigue

258

Type of periodic paralysis caused by decreased blood K+ during paralytic episodes

Hypokalemic periodic paralysis

259

Type of periodic paralysis caused by normal or increased blood K+ during paralytic episodes

Hyperkalemic periodic paralysis

260

Which skeletal muscle type is comprised for slow twitch fibers (high blood flow, lots of mitochondria, fatigue resistant)

Type I

261

Which skeletal muscle type is comprised for fast twitch fibers that receive HIGH blood flow and HIGH mitochondrial content (relatively fatigue resistant)

Type IIa

262

Which skeletal muscle type is comprised for fast twitch fibers that receive LOW blood flow and LOW mitochondrial content (fatigue rapidly)

Type IIb

263

Disorder where patient creates autoantibodies against nicotinic acetylcholine receptors creating muscle weakness mostly in eyelids and mouth region is called what? What do we use to treat it?

Myasthenia gravis
Treat with acetylcholinesterase inhibitor

264

how are mtDNA inherited differently from nuclear DNA

we got it from our MAMA (also we have multiple copies per cell)

265

most common mitochondrial disease: subacute loss of vision in young adults (mostly men) due to mutation in gene encoding for complex I subunits

Leber's Hereditary Optic Neuropathy (LHON)

266

this disease can be caused by mutations in nuclear or mitochondrial DNA that code for complex I or IV presenting as developmental delay, respiratory abnormality, recurrent vomiting, nystagmus, ataxia, dystonia, early death

Leigh's Syndrome.... 90% of mtDNA contains mutation

267

multisystem mitochondrial disorder where brain, muscle, endocrine are involved leading to death in young adulthood. symptoms include stroke like episodes (infarct in temporal and occipital lobes). this is an angiopathy. Treat with L-arginine to decrease stokes.

mitochondrial encephalomyopathy, lactic acidosis, and stroke like episodes (MELAS)

268

mitochondrial disorder where mutations occur in tRNA for lysine. symptoms: cervical lipomas, myoclonus, epilepsy, COX negative

Myoclonus epilepsy and ragged red fibres (MERRF)

269

what are canonical features of mitochondrial OXPHOS disorders?

recessive inheritance, reduction in cellular oxygen consumption and ATP synthesis, increased resting lactic acid, overproduction of ROS, sometimes induce autoimmune response

270

all mtDNA is encoded to create what

OXPHOS system

271

who carrie sub threshold levels of potentially harmful mtDNA mutations

normal humans like you and me - we get more as we age

272

what type of mutation auses MELAS

A to G in gene for tRNA for leucine

273

what type of mutation auses MERRF

A to G in gene for tRNA Lys

274

what tissues are most likely to accumulate mtDNA mutations

postmitotic tissue (brain, heart, muscle)

275

what important cancer causing gene also regulates respiratory chain function and glycolysis via regulating transcription and making SCO2 (loss of this gene stimulates glycolysis and TCA cycle)

p53

276

whats the crabtree effect

p53 mutation causes cancer cells to prefer glycolysis and TCA cycle and suppress OXPHOS

277

Warburg hypothesis states that mutation in nDNA encoding which two TCA cycle intermediates can lead to cancer

succinate dehydrogenase, fumarase

278

a defect in the gene product of MELAS patients

tRNA for leucine or ND1

279

a defect in the gene product of MERRF patients

tRNA for lysine

280

a defect in the gene product of LHON patients

NADH ubiquinone oxidoreductase (N1)

281

how are transmitochondiral lines created for studying mitochondrial disease and mutation load of mitochondrial mutations

making cybrids: injecting mtDNA of sick pt into empty mitochondria

282

what is the phenotypic threshold value for mtDNA deletions? for mtDMA mutations?

60% for deletions
90% for mutations

283

different tissues have different thresholds for phenotype of mtDNA mutations. which has a higher threshold: brain or heart tissue?

heart!

284

What medication do we give in emergent situation of malignant hypothermia?

Dantrolene (blocks Ryanodine receptor)

285

cox positive mt disease

melas

286

cox negative mt disease

merrf

287

mt disease that has the red ragged fibers

merrf

288

mt disease with strokes due to angiopathy

melas

289

complex I mutation mt disease leads to blindness

lhon