Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

37 Cards in this Set

  • Front
  • Back
part of the muscleGenerates force
individual muscle cells, body contains them in bundles
`hundreeds or thousands of muscle cells
muscle fibers
muscle fiber's plasma membrane
contain fiber's contractile machinery. A bundle of overlapping thick and thin filaments made of proteins.
surrounds each of the myofibrils
sarcoplasmic reticulum
connected to the sarcolemma and penetrate into the cell's interior
transvers tubules (T tubles)
skeletal muscle cells have a striped appearance
striated muscle
fundamental unit that compose myofibrils
2 proteins that make up thin and thick filaments
actin and myosin
actin and myosin, generates contractile force
contractile protein
enable muscle fibers to start or stop contracting
regulatory proteins
extends over numerous actin molecules in such a way that it blocks the myosin-binding sites in a muscle at REST
complex of 3 proteins
1. attaches to the actin strand
2. binds to tropomyosin
3. contains a site where Ca ions can bind reversibly
bridge the gap between the thick and thin filaments
binding to the actin monomers in the thin filaments
actin-binding site
ATPase site
extraordinarily elastic protein that can be stretched to more than 3x's its unstressed length
muscles contract because the thick and thin filaments of the myofibrils slide past each other
sliding-filament model
mechanism that drives the sliding of thick and thin filaments past one another
corssbridge cycle
myosin molecuel sotres energy that is relased in the hydrolytic splitting of ATP
High-energy form
myosin heads go into the other conformation, after the stored energy is realeased to drive the movement of the thin filaments
low-energy form
sequence of events that lanks the action potential to the contraction
excitation-contraction coupling
Opposite terminal bouton in region of sarcolemma, highly folded and contains a high density of acetylcholine receptors
motor end plate
Link T tubles and SR membranes, bridge gap b/w the the two and also function as Ca channels
foot structures - ryanodine receptors
where teh foot structures come inot contact w/the T tubule membranes, function as volatge sensors
dihydropyridine receptors - DHP receptors
immediately available sotre of high-energy pohsphate that is present in the form of this compound
creatine phosphate
reproducible, all or nothing event; if the cell is stimulated again, it gives the identical response. ALL skeletal muscles built upon this
mechanical response of an individual muscle cell, a motor unit, or a whole muscle to a singel action potential
a motor neuron and all the msucle fibers it innervates
motor unit
delay of a few milliseconds that occurs b/w the action potential in a muscle cell and the start of contraction...first begins to generate force
latent period
starts at the end of the latent period and ends when musclular tension peaks
contraction phase
longest of the 3 phases, time b/w peak tension and the end of the contraction, cytosolic Ca levels are Decreasin as reuptake exceeds release number of active crossbridges decrease
relaxation phase
generates a tension at least equal to any forces opposing it, mesucle shortens
creates tension but does not shorten because the load is greater than the force generated by the muscle
carcomers collectively
contractile component, CC
parts of a muscle that do not actively generate force but oly serve to passively transmite force to the ends of the muscle
series elastic components SEC