threadlike structure, running longitudinally through a muscle fiber (cell) and consisting mainly of thick myofilaments (myosin) and thin myofilaments (actin, troponin, tropomyosin)
Long, highly organized contractile bundle of actin, myosin, and other proteins in the cytoplasm of a muscle cell; contracts by a sliding-filament mechanism.
(my´ oh fy´ bril) [Gr. mys: muscle + L. fibrilla: small fiber] • A polymeric unit of actin or myosin in a muscle.
Long, highly organized bundle of actin and myosin filaments and other proteins that constitute the basic structural unit of muscle cells (myofibers) ( Figure 22-26)
a protein fibril of muscle cells which is able to contract. It is made of many threads of protein.
(mi'-o-FI-brihl) A rod-shaped component of a muscle fiber, which extends the length of the fiber and is composed of thin and thick filaments of protein.
One of many fibrils consisting mainly of protein that filla muscle fiber.
Organized collections of myofilaments in skeletal and cardiac muscle cells.
one of many contractile filaments that make up a striated muscle fiber
Myofibrils are very small fibers that run through each muscle fiber. The myofibrils have alternate light and dark bands, which contain protein filaments responsible for the muscle's contractile ability and give the muscle its typical striped appearance under the microscope.
( my-oh- fy-bril) [Gk. mys, muscle + L. fibra, fiber] A fibril collectively arranged in longitudinal bundles in muscle cells (fibers); composed of thin filaments of actin and a regulatory protein and thick filaments of myosin.
The functional units within muscle fibers that cause contractions; The more myofibrilla (plural) a person has, the greater his or her strength.
A bundle of thick and thin filaments that forms an organizational unit within a single muscle cell, which contains several myofibrils.
Long cylindrical organelle of striated muscle, composed of regular arrays of thick and thin filaments, and constituting the contractile apparatus.
Longitudinal unit within a muscle fiber
Myofibrils (obsolete term: sarcostyles) are cylindrical organelles, found within muscle cells. They are bundles of filaments that run from one end of the cell to the other and are attached to the cell surface membrane at each end.
