Identify the connective tissue sheath surrounding a single skeletal muscle fiber.

Identify the connective tissue sheath surrounding a single skeletal muscle fiber.

• A. Endomysium
• B. Perimysium
• C. Epimysium
• D. Fascia

Answer: (A)

Skeletal muscle fibers are wrapped by progressively larger connective tissue layers, each serving a distinct organizational level. The layer around an individual muscle fiber is a very delicate sheath that lies just outside the sarcolemma and contains capillaries and small nerve fibers. This is the endomysium. It provides mechanical support to each fiber and helps create the microenvironment for the fiber’s metabolic needs, including pathways for blood supply and satellite cells for repair. If you move outward, the next layer surrounds a group of fibers called a fascicle, and is the perimysium. The outermost layer that encloses the entire muscle is the epimysium. Fascia is a broader connective tissue sheet that surrounds groups of muscles or muscle compartments. So the connective tissue sheath surrounding a single skeletal muscle fiber is the endomysium.

Skeletal muscle fibers are wrapped by progressively larger connective tissue layers, each serving a distinct organizational level. The layer around an individual muscle fiber is a very delicate sheath that lies just outside the sarcolemma and contains capillaries and small nerve fibers. This is the endomysium. It provides mechanical support to each fiber and helps create the microenvironment for the fiber’s metabolic needs, including pathways for blood supply and satellite cells for repair.

If you move outward, the next layer surrounds a group of fibers called a fascicle, and is the perimysium. The outermost layer that encloses the entire muscle is the epimysium. Fascia is a broader connective tissue sheet that surrounds groups of muscles or muscle compartments. So the connective tissue sheath surrounding a single skeletal muscle fiber is the endomysium.