Sarcomere extends between
The area between two adjacent Z lines is called a sarcomere. The thick filaments are lined up to form the A bands, whereas the array of thin filaments extends out of the A band and into the less dense staining I bands.(REF.GANONG'S REVIEW OF MEDICAL PHYSIOLOGY -23rd EDITION. Page No-95.)
A band & I band
Two Z lines
Two I bands
None
General physiology