Muscle Tissue
Muscle: A bundle of muscle fibers that have the power to contract and hence to produce movement.
Muscle Fascicle: A bundle of axons in a nerve surrounded by the perineurium.
Muscle Fiber: An alternate name for a skeletal muscle cell.
Myofibril: performs muscle contraction
Myofilament: regulators of contractions. forces production and motion.
Sarcomere: composed of actin and myosin and is a contractile muscle fiber unit
Endomysium: The connective tissue covering an individual muscle fiber.
Perimysium: The connective tissue covering around a fascicle.
Epimysium: The connective tissue covering on the outside of a whole muscle.
Sarcoplasmic Reticulum: The specialized smooth endoplasmic reticulum of a muscle fiber that stores calcium ions.
A band: striated muscle sarcomere that contains myosin thick filaments
H zone: The zone of the thick filaments that has no actin
I band: The zone of thin filaments that is not superimposed by thick filaments
M line: attachment site for the thick filaments.
Myosin – heavy chain: motor proteins that power smooth muscle contraction
Actin – light chain: generate forces on the filaments to support muscle contraction.
ATP : energy carrying molecule that captures chemical energy obtained from the breakdown of food molecules and transfers it to cellular processes. Binding to Myosin thick filaments to produce power stroke.
Sarcolemma: acts as a barrier between the extracellular and intracellular compartments
Sarcoplasm: Cytoplasm of a muscle fiber that suspends necessary factors to muscles
T-Tubule: role is to maintain the SR calcium store under the tight control of membrane depolarization via the voltage sensor channel
Titin: gives elastic stabilization of relative positions of myosin and actin filaments
Dystrophin: part of a protein complex that strengthens muscle fibers and protect them from injury as muscles contract and relax
Nebulin: actin binding protein that may act as a regulator of thin filament length
Tropomyosin: regulates muscle contraction and relaxation through its interactions with actin, myosin, and the troponin complex
Troponin: Regulates calcium in skeletal and cardiac muscles