Microscopic Cardiac Muscle Tissue Model

Z-Line/Z-Disc

Only thin/Actin filaments

I-Band

Only thin/Actin filaments

A-Band

Myosin (thick) filaments/Actin (thin) filaments

H-Zone

Myosin filaments

M-Line

Myosin filaments and accessory proteins

Myosin Filament

Form the 'arms' that pull the actin fiber framework towards the M-line during contraction/ aid in muscle contraction

Actin Filament

Forms the framework that is pulled by the myosin filaments machinery/ aid in muscle contraction

Sarcoplasmic Reticulum (SR)

Repository for Ca++

Transverse Tubule

Propagates action potential close to the sarcoplasmic reticulum

Transverse Tubule Opening

Opening that allows action potential to get close to the sarcoplasmic reticulum

Sarcolemma

Protects/guards the interior of the muscle cell/ propagates action potential to the T-tubules

Sarcoplasm

Holds Nucleus/ holds organelles

Mitochondrion

Powerhouse of the cell/ supplies muscle cell with ATP

Glycogen Granules

Used to produce ATP/ energy stores

ACTIN AND MYOSIN FILAMENTS (IN-A-BAND)

Contraction of the muscle