514-8 Muscle Phys Flashcards
What are 2 synonyms for a muscle cell?
Myofiber & Muscle Fiber
What are the cells in between the sarcolemma and the endomysium that are mesenchymal in origin and can help repair the cell if damaged?
Satellite Cells!
What protein blocks the active site on actin?
Tropomyosin
What is another name for the Neuro Muscular Junction?
Terminal Bouton
What does calcium bind to on actin to RELEASE tropomyosin and expose the active site?
Troponin. SO Calcium->Troponin->Tropomyosin->myosin binds to actin
What is the key word in myofiber development?
Syncytial development
Where are the terminal cisternae located?
At the meeting of every A band and I band
What is a triad composed of?
1 T-tuble and 2 cisternae…Look for them at the meeting of the A band and the I band!!
Does the H zone have any myosin heads present?
Nope
What are the three classes of proteins in a muscle cell?
Regulatory(Troponin,Tropomyosin) Contractile(Actin,Myosin) & Elastic (Titin)
Which zones shrink during contraction? Which zones stay the same?
H and I shrink, A stays the same
How many axon branches make a muscle fiber contract?
One
How many muscle fibers are innervated by the same neuron in a large motor unit? Small motor unit?
Large:1000+ small:3-6 muscle fibers per nerve fiber
What do pesticides block?
AChesterase, ACh doesn’t get degraded so constant tetanus
How does tetanus bacterial toxin work?
Blocks glycine
