Figure 7-1 Structural Components of a Skeletal Muscle Fiber

Figure 7-1 Structural Components of a Skeletal Muscle Fiber
Use Figure 7-1 to identify the labeled part.
-The triad, seen as structure D, is composed of

A) the T tubules and the myofibrils.
B) actin and myosin.
C) troponin and tropomyosin.
D) the cisterna of the sarcoplasmic reticulum along with the T tubules.
E) the cisterna of the sarcoplasmic reticulum and the myofilaments.