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

17 Cards in this Set

  • Front
  • Back
a muscle fiber is composed of thousands of stacked, cylindrical, contractile structures called
each myofibril consists of smaller contractile units called
each sarcomere contains an orderly arrangement of rod-like protein filaments called
2 types of myofilaments
myosin protein (thick) - actin protein (thin)
what give skeletal muscle it's striated appearance
actin + myosin
sarcoplasm description/function
similar to cytoplasm - contains myoglobin
myoglobin description/function
red protein pigment - stores oxygen
sarcolemma description/function
plasma membrane of muscle fiber - carries impulses initiated by nerves
t-tubules description/function
extensions of sarcolemma - conduct impulses deep into muscle fiber
sarcoplasmic reticulum description/function
system of ER surrounding each myofibril - stores calcium
what are calcium ions need for
muscle contraction
terminal cisternae description/location
widened regions of sarcoplasmic reticulum - surrounds each t-tubule
sarcomere is the smallest
contractile unit
filaments that constitute myofibrils
3 myofilament characteristics
each thick filament surrounded by thin - thick + thin overlap in some areas - causes striations
sarcomere extends from ____ to ____
z-line to z-line or discs
z-line (band) 2 details
protein sheet anchors actin filaments - attaches 1 sarcomere to another