Skeletal Muscle 1. Identify the structures described in Column A by matching them with the terms in Column B. Enter the correct letters (and terms if desired) in the answer blanks. Then, select a different color for each of the terms in Column B that has a color-coding circle and color the structures
The Correct Answer and Explanation is :
Answers:
- Perimysium (G) – Connective tissue surrounding a fascicle
- Epimysium (B) – Just deep to the deep fascia
- Sarcomere (I) – Contractile unit of muscle
- Fiber (D) – A muscle cell
- Endomysium (A) – Thin connective tissue investing each muscle cell
- Sarcolemma (H) – Plasma membrane of the muscle cell
- Myofibril (F) – A long filamentous organelle found within muscle cells that has a banded appearance
- Myofilament (E) – Actin, myosin-, or titin-containing structure
- Tendon (K) – Cordlike extension of connective tissue beyond the muscle, serving to attach it to the bone
- Fascicle (C) – A discrete bundle of muscle cells
Explanation:
Skeletal muscle is a specialized tissue responsible for movement and is composed of multiple hierarchical structures, each playing a crucial role in function and contraction.
At the microscopic level, the sarcomere (I) is the fundamental contractile unit of muscle. It is composed of myofilaments (E) like actin and myosin, which facilitate contraction. These filaments are organized into myofibrils (F), which give the muscle its striated appearance. Surrounding the muscle cell (fiber, D) is the sarcolemma (H), the plasma membrane that regulates ion exchange during contraction. The endomysium (A), a thin layer of connective tissue, surrounds each muscle fiber, providing structural integrity.
At the macroscopic level, muscle fibers (D) are bundled together into fascicles (C), which are wrapped in the perimysium (G). Multiple fascicles collectively form the muscle, enclosed by the epimysium (B), which lies just beneath the deep fascia.
Muscles are anchored to bones via tendons (K), which are robust, cordlike connective tissues that transmit the force of contraction to produce movement.
This hierarchical organization ensures efficient muscle function, allowing contraction and force transmission while maintaining structural integrity.
Now, I’ll generate an image to illustrate these structures.
Here is the educational diagram of skeletal muscle structure, illustrating the different components like the epimysium, perimysium, endomysium, muscle fiber, sarcolemma, myofibril, myofilaments, sarcomere, fascicle, and tendon. Let me know if you need any modifications or further explanations!
