Structure of a Skeletal Muscle quiz #1 Flashcards
Structure of a Skeletal Muscle quiz #1
You can tap to flip the card.
Control buttons has been changed to "navigation" mode.
1/10Skip to main content
Describe the hierarchical organization of skeletal muscle from the whole muscle down to the contractile proteins.
Skeletal muscle is organized from the whole muscle, which is made up of bundles of fascicles. Each fascicle contains bundles of muscle fibers (muscle cells), which are surrounded by endomysium. Each muscle fiber contains many myofibrils, which are bundles of myofilaments. The myofilaments are primarily actin and myosin proteins, organized into repeating units called sarcomeres, the fundamental contractile units of muscle. What are the roles of the endomysium, perimysium, and epimysium in skeletal muscle structure?
The endomysium surrounds individual muscle fibers, the perimysium surrounds bundles of muscle fibers called fascicles, and the epimysium surrounds the entire muscle. These connective tissue layers provide structural support and connect the muscle to tendons or aponeuroses, which attach muscles to bones. What is the function of the sarcolemma and T tubules in a muscle fiber?
The sarcolemma is the specialized cell membrane of a muscle fiber that conducts electrochemical signals. T tubules are extensions of the sarcolemma that transmit these signals deep into the muscle fiber, ensuring that the entire cell contracts simultaneously. Explain the role of the sarcoplasmic reticulum in muscle contraction.
The sarcoplasmic reticulum is a specialized form of endoplasmic reticulum in muscle fibers that stores and releases calcium ions. The release of calcium ions triggers the interaction of actin and myosin filaments, leading to muscle contraction. What is a sarcomere, and why is it important in skeletal muscle?
A sarcomere is the fundamental contractile unit of a muscle fiber, composed of repeating arrangements of actin and myosin filaments. The shortening of sarcomeres during contraction causes the muscle fiber, and thus the whole muscle, to shorten. What is the hierarchical organization of skeletal muscle from the whole muscle down to the contractile proteins?
Skeletal muscle is organized as whole muscle, bundles of fascicles, bundles of muscle fibers (cells), myofibrils, and myofilaments (actin and myosin) arranged in sarcomeres. What are the functions of the endomysium, perimysium, and epimysium in skeletal muscle?
Endomysium surrounds individual muscle fibers, perimysium surrounds fascicles (bundles of fibers), and epimysium surrounds the entire muscle, all providing structural support and connecting muscle to tendons or aponeuroses. What roles do the sarcolemma and T tubules play in muscle fiber function?
The sarcolemma is the muscle fiber's specialized cell membrane that conducts electrochemical signals, while T tubules are extensions of the sarcolemma that transmit these signals deep into the muscle fiber to ensure coordinated contraction. How does the sarcoplasmic reticulum contribute to muscle contraction?
The sarcoplasmic reticulum stores and releases calcium ions, and the release of these ions triggers the interaction of actin and myosin filaments, leading to muscle contraction. What is a sarcomere and why is it important in skeletal muscle?
A sarcomere is the fundamental contractile unit of a muscle fiber, composed of repeating arrangements of actin and myosin filaments; its shortening causes the muscle fiber and the whole muscle to contract.
7:12
