A-I junction

The A-I junction is the junction between the A and I bands of the sarcomere, which is the smallest unit of a muscle fiber. In skeletal muscle, the T tubule, an extension of the skeletal muscle plasma membrane, is located here.

A-I junction

The A-I junction is the junction between the A and I bands of the sarcomere, which is the smallest unit of a muscle fiber. In skeletal muscle, the T tubule, an extension of the skeletal muscle plasma membrane, is located here.