BMS 250 Chapter Notes - Chapter 10: Cytosol, Neuromuscular Junction, Extracellular Fluid
Document Summary
The overlapping myofilaments form unique patterns of alternating light and dark regions within a skeletal muscle fiber. When a longitudinal section of skeletal muscle tissue is viewed in a microscope is appears striped/. This striated appearance is due to both the size and density differences between thin filaments and thick filaments. Other structural and functional proteins: there are proteins that have structural and functional roles within muscle fibers. Connectin: also called, titin, is a cabelike protein that extends from the z discs to the m line through the core of each thick filament. It stabilizes the position of the thick filament and maintains thick filaments within a sarcomere. Additionally, portions of the connectin molecules are coiled and springlike so that during sarcomere shortening they are compressed to produce passive tension. This passive tension is then released to return the sarcomere to its normal resting length.
