MSK

Question 1

Skeletal muscle

Answer 1

attaches to bone and skin

*YES striations

Question 2

Cardiac Muscle

Answer 2

walls of the heart

*YES striations

Question 3

Smooth muscle

Answer 3

walls of hollow organs; eye muscles, airways and large arteries, stomach

*NO striations

Question 4

Structure & Organizations of Muscle layer

Answer 4

muscle
fascicle
muscle fiber / cell

Question 5

Connective Tissue wrappings

Answer 5

Muscle (epimysium)
Fascicle (perimysium)
Muscle Fiber (endomysium)

Question 6

Sarcolema

Answer 6

plasma membrane

Question 7

myoglobin

Answer 7

oxygen storage

Question 8

glycosome

Answer 8

glycogen / glucose storage

Question 9

Sarcoplasmic Rediculum

Answer 9

fluid filled membrane channels that are wrapped around the myofibrils

Question 10

T tubules

Answer 10

ingavinations of the sarcolemma, forms a closed tunnel system throughout the uscle that contains Extracellular fluid

Question 11

triad

Answer 11

junction of T tubule with the SR on each side

Question 12

I band

Answer 12

where there are two thin filaments

*straddles 2 sacromeres

Question 13

Z line

Answer 13

arrays of thin filaments are attached to one end

Question 14

H zones

Answer 14

portion of the A band that does not have thin filaments

Question 15

A band

Answer 15

where there is some overlap of thin and thick filaments

Question 16

Actin

Answer 16

thin filament

Question 17

Myocin

Answer 17

Thick filament

Question 18

elastin

Answer 18

coiled = contracted
relaxed = stretched

Question 19

Tyopomyocin and troponin

Answer 19

proteins that regulate contraction, they are bound to actin

Question 20

tropomyosin

Answer 20

regulatory protein
prevents binding of myosin

Question 21

troponin

Answer 21

helps initiate muscle contraction

binds to calcium and tells them to move

Question 22

Titin

Answer 22

elastic filaments are made up of a protein called titin

Question 23

titin function

Answer 23

hold thick filaments in place
help muscle recoil after stretch
protect the muscle from excessive stretch

Question 24

Nebulin

Answer 24

support protein that anchors actin

Question 25

myomesin

Answer 25

anchors myosin (thick) filaments

Question 26

Desmin

Answer 26

links myofibrils and connects them to cell membrane

Question 27

C proteins

Answer 27

located in thick filament of sarcomere mutations: encode cardiac versions of myBP-C which are associated with cardiomyopathies

Question 28

motor end plate

Answer 28

sarcolemma at the site of NMJ

Question 29

end plate potential

Answer 29

the binding of ACh to nicotinic receptors causes a graded potential called an end plate potential

Question 30

Neuromuscular Junction Events

Answer 30

1. Ap arrives at axon terminal 2. Voltage gated calcium channels open, calcium enters motor neuron 3. Calcium entry causes release of ACh neurotransmitter into synaptic cleft 4. ACh diffuses across to ACh receptors (NA chemical gates) on sarcolemma 5. ACh binding to receptors, opens gates, allowing Na+ to enter resulting in end plate potential 6. Acetylcholine sterase degrades ACh

Question 31

Achtylcholinesterase pathology...

Answer 31

tetanus... (cannot uncontract) Botulinum toxin (unable to contract)

Question 32

Where is the calcium causing the muscle contraction coming from

Answer 32

Sarcoplasmic reticulum

Question 33

General actions of an Action Potential

Answer 33

action potential depolarization Ryr (ryanodine receptor causes lease from SR) activation receptor calcium leaves Sarcoplasmic reticulum

Question 34

Cross Bridge Cycling

Answer 34

1. energized myosin attaches to an actin myofilament... this forms a new cross bridge 2. ADP and P are released and myosin head pivots and bends... changing to its bent low-energy state. as a result it pulss the actin filament toward the M line... 3.After ATP attaches the link between myosin and actin weakens... and the myosin head? 4. ATP is hydrolyzed to ADP and P the myosin head returns to its prestorke high-energy "cocked" position

Question 35

Low intracellular Calcium

Question 36

Tennis arm muscle

Answer 36

Overworked Extensor Carpi radialis

Question 37

Most frequently injured rotator cuff muscle

Answer 37

supraspinatus muscle

Question 38

schwann cells

Answer 38

principle glial cells of peripheral nervous system

Question 39

Satellite cells