muskuloskeletal Flashcards
sliding filament theory steps
1)an AP crosses the NMJ
2) Ca2+ channels open ( released from the SR
3) Ca2+ unlocks tropomyosin exposing ht emyosin head binding sites
4) ATP binds to the myosin heads –> ADP +P “ COCK & BIND)
-power stroke occurs
*requires more ATP to do again
what are the 3 types of muscle tissue?
cardiac: involuntary, has intercalated discs and 2 nuclei, striations
Smooth: involuntary, no striations (organs)
skeletal: multinucleate, striations, alpha motor neurons
Epimysium?
surrounds the entire skeletal muscle
Perimysium?
surrounds muscle fassicle
endomysium?
surrounds muscle fiber
muscle fiber
muscle cell
sarcolemma
plasma membrane
end plate
where the alpha motor neuron connects w the muscle fiber
SR?
the ER of the muscle ccell, a lot of Ca2+, and VG Ca2+, & transports for Ca2+
T-tubules
extension of the sarcolemma
sarcomere
contractile unit of the muscle cell made up of myofilaments ( striated appearance)
what do I -bands poses at rest only?
actin
what do A-bands poses at rest?
myosin & actin
z-discs?
end of the sarcmere ( attment points for the atin filaments.
H-zone only has __ at rest?
myosin
myofilaments?
actin: thin filament, F-fibrous(2 chains) G-globular= winds together= helix
myosin: thick filament heads bind to actin, heads appear every 60 degrees need Ca2+ to bind
myofilament associate proteins
tropomyosin: winds around f-actin and blocks troponin (bind sites)
troponin: has 3 binds sites
-C-Ca2+
A-Actin
T-tropomyosin
what are some skeletal muscle properties?
excitable, elastic, extensible, contractable
functions:
movement, joint stability, organ system, protection, thermoregulation
NMJ
chemical synapes between alpha motor neuron and the motor end plate of the muscular fiber
small motor unit
alpha motor neuron innervates onle a few fibers
- more fine control, small representation in the primary otor cortex
motor end plate has lots of____ channels
ioniotropic nicotinic ACH receptors ( LG Na+)
what is the RMP?
-90mv
excitation contraction coupling
ap—> neuron terminal—> Ca2+ channels open—-> ACH binds ot NaChR on motor end-plate, Na+ enters muscle cell=graded potential–> muslce Ap—> K+ in to repo
return after excitation:
Ap–> alog the sarcolemma–> t-tubules—> vg Ca2+ on SR open moves ca@= back–> needs ATP to occur
sources of ATP
- creatine phosphate= #1
when muscles at rest the excess ADP + P transfers the p to creatine
when muscle =active kinase removes hte p from creatine phosphate—> ATP - anerobic metabolism: breakdown of c6h12o6 #2
connective tissue components:
- epi/peri/endomysium
-tendons: muscle bone to bone, fibrous/rigid
-tendon sheaths: doubed walled tubes of ct (ankle)
ligaments: bone to bone, fibrous/rigid
fascia: the ct surrounding an organ under the subq
parallel muscle shape:
sartouris
Convergent:
pectoralis major
pennate
rectus femoris
fusiform
Brachioralidis
spiral
latissimus dorsi
circular
orbicularis oris
origin
the POI for a muscle
insertion
point of attachment that moves along the line of the force
prime mover
muscle that directly performs a specific movement
antagonist
when many muscles directly oppose the prime mover ( relaxed when the prime mover contracts)
synergist
contracts at the same time as prime mover
fixator muscle:
jooint stabalizer
all levers have…. (4)
lever, pivot, load, force
1st class lever example:
head on atlas
2nd class lever ex:
wheel barrow
3rd class lever:
lat raises
irregular bones
irregular porjections & vary in size ( spine)
long bones
long hallow shaft w/ 2 bulbous ends ex: humerous
short bones
square like shape and found in the hand
flat bones
reltively thin and curved , skull bones
boney matrix
made of haversion system or osteons = microscopic structures
complete fracutre
bone divides into 2
transverse fraction
split across the bone
spiral fracture
eide diagonal aorund the bone
communicated fracutre
multiple breaks in 1 bone
green stick fratures ar emost common in ____
kids
colles fracture is a fracture of the ____
distal radius
fracture healing process
1) blood pools, hematoma forms, inflammation(week 1)
2) soft cartillage forms (week 2-3)
3) calus forms stablizing the bone(week 4-26)
4) osteoblasts/clasts continue remodeling (week 17)
compartment syndrome:
damage to muscle tissue causing major bleeding trapped within the fascia, too tight and can not expand, increased swelling compresses BV/nerves—> ischemia
what are the 5 p’s of compartment syndrome
pain, pallor, parenthesia, paralysis, pulselessness
compartment syndrome is most common in___
crush injuries; releases myoglobin (toxic to kidneys)—> AKF/Hear arrhythmias
dislocation
separation of articulation between two bones
subluxation
partial dislocation, bone moved from og position though not fully detached
osteoporosis
reduction of bone density, bones become more porous, most common in older women going through menopause, hormonal imbalances, lack of Ca2+, PTH decrease, high likely hood to break bones
rickets
deficiency of Ca2+/vit D in kids—> misshappen bones
osteoalacia
rickets in adults
osteomyelitis
infection of bone tissue caused by bacterial–> inflammation, necrosis, fracutres
osteosarcoma
bone cancer–> easily breads to other tissues, begins in the metaphysis, more common in long bones
lordosis
major low curvature of lower spine
kyphosis
upper curvature of cspine
scoliosis
medial lateral curve of spine
osteoarthritis:
lack of articular cartillage on connecting bones making connttact w eachother, joint space will increase over time–>crepitus
- most common in knees, obesity,elderlym acute trauma, hereditery, rheumatoid arthritis, diabetics, surgery,
osteoarthristis is degernative w no systemic inflmmatory signs (t/f)
true
early osteo arthritis s/s
mild pain with weight bearing, joint stiffness after inactivty/ waking up, onset can be unilateral—> bilateral
mid s/s of osteoarthritis
moderate pain w weight bearing, reduced movement & loss ofmuscle tone, osteophytes & bone spurs
late osteoarthritis s/s
creptius, joint disfiguration, comple loos of space between oins, bone-bone contact
rehumatoid arthritis
autoimmune disorder most common in females, type 3 hypersensitivity, antibodies made for blood borne markers causes osteoclats to erode bones
Insidious onset, bilateral discomfort, stiffness, inflammation in small joints, ulnar drift etc.
ankylosing spondylitis
autoimmune common in males, effects the intervertebral discs starting at sacrum–> fuse vertebrae–> osteoporosis/kyphosis
low back pain, sciatica pain, inflammation, can affect the eys, GI complications, etc
Tx: pain relief, moderate exercise, anti-inflames
Duchenes muscular dystrophy:
x-linked recessive disorder affects men, altered dystrophin protein on gene, weak muscles by age 3 in pelvis legs,
what does dystrophin dysfunction do?
affects the power stroke of actin and myosin, causes poor tendon reflexes, fat deposits in muscles, cardiomyopahty, khyphois/scoliosis
kids who toe walk at age 3 with poor reflexes, and unstable pelvis most likely have
duchenes muscular dystrophy
fibromyagia
occurs in women more, ages 20-50, no obvious inflammation, no common patho, Soft tissue pain, tendons but no bones/joints, 18 trigger points to promote episodes, headaches, sleep disorders, N/V
compact bone:
outer layer surroundign bone and majes u the hard matrix
osteoblasts_____ & osteoclasts______? (functions)
Build boney matrix & breakdown boney matrix
cancellous bone
iside of bone, matrix= made up of trabecular scafolding, Yellow & red bone marrow
periosteum
tissues that surrounds compact bone & has nerves and bV
endosteum
lines the inside of the compact bone in diaphysis of long bone
medullary cavity
inside of diaphysis
bone growth
occurs along the ephyseal plate, cells start as chondrocytes in cartillingous matrix, cartillingous tissue ossfies, bone remodelling & balance of osteoblasts/clatss.
Ca2+ homeostasis
low–> osteoclast—> reabsorb more boney matrix under influence of PTH and Vit d
high–> osteoclast stopped by calcitonin—> osteoblasts ++ matrix production
function of bones
support/protection, movement, hemopoiesis, storage for minerals & salts
cells of bones
osteoprogenitior cells: stem cells —> mature into osteoblasts
ossteoblasts & osteocyctes
blood is a dense connective tissue (t/f)
true
spongy bone makes up 80% of bone (t/f)
false, Compact bone, spongy=20%
hyaline cartillage can be found….
in the ribs, growth plate, ends of some bones
fibro cartillage can be found….
in the intervertebral discs
how many vertebrae are there?
26 (2 fused)
