Striations

When used in the context of the anatomy of muscle structures, the word striations refers to the stripe-like visual features found in skeletal muscle.

These visual features consist of alternating light and dark striations that can be observed using just a simple light microscope.

These striations are due to the highly ordered arrangement of actin and myosin filaments within each myofibril and the orderly arrangement of the myofibrils within the muscle cell (fibre).

Each line or set of lines is given a letter name, which is the accepted way to refer to specific parts of these striations. These letter names are:

• A band,
• H zone,
• I band and
• Z disc.

Other types of muscle tissue:

There are three main types of muscle tissue.
They are:

• Skeletal Muscle - muscles that move bones, under concious control.
• Smooth Muscle - surrounding organs and other body structures, not under concious control.
• Cardiac Muscle - the specialized muscle found only in the heart.