Microscopic Anatomy of Skeletal Muscle

Bachelor of Science in Medical Technology (1st Year): HUMAN ANATOMY AND PHYSIOLOGY WITH PATHOPHYSIOLOGY

• Skeletal muscles are multinucleate, by which oval nuclei can be seen beneath the _________ (also known as muscle hast; outermost covering of the skeletal muscle).

sarcolemma

• The nuclei are pushed aside by long ribbonlike

  organelles called _____ (nuclei are pushed

  aside; composed of alternating light and dark).

myofibrils

• Alternating _____________ bands give the muscle cell its striated appearance.

light (I) and dark (A)

• The light I band has a midline interruption called the _____

Z disc

• The dark A band has a lighter central area called the ______

H zone/bare zone

• In the __________, contains tiny protein rods that hold adjacent thick filaments together.

Center of the H zone

• Structural and functional units of skeletal muscle.

• Responsible for the striations of skeletal muscle.

Sarcomeres

• extend the entire length of dark A band.

Thick filaments (myosin filaments)

• anchored to the Z disc.

Thin filaments (actin filaments)

• The _______ contains only the thin filaments.

light I band

• Contain 2 proteins

• These overlap together that forms striations.

tropomyosin & troponin