What causes the striated appearance of skeletal muscles?

Best   Sarcomeres

"The sarcomeres are what give skeletal and cardiac muscles their striated appearance.

A sarcomere is defined as the segment between two neighbouring Z-lines (or Z-discs, or Z bodies). In electron micrographs of cross striated muscle the Z-line (from the German "Zwischenscheibe", the band in between the I bands) appears as a series of dark lines

As what he you go get the hot dog ; )