Jackson County Donates to Special Olympics Jackson County associates made a donation of $400 to Special Olympics. Parks + Rec also donated 600 boxes of candy to the cause.
Transverse tubules are extensions of the cell membrane that penetrate into the centre of skeletal and cardiac muscle cells. With membranes that contain large concentrations of ion channels, transporters, and pumps, T-tubules permit rapid transmission of the action potential into the cell, and also play an important role in regulating cellular calcium concentration. Through these mechanisms, T-tubules allow heart muscle cells to contract more forcefully by synchronising calcium release throughout
See Excitation-contraction coupling. T-tubules are the major sites for the coupling of excitation and contraction, which is the process whereby the spreading depolarization is converted into force production by muscle fibers.ransverse tubules are invaginations of the sarcolemma. Though the invaginations are normally perpendicular to the length of the fiber, many T-tubules can lie axial to the long-axis of the fiber, both wrapping around and running alongside myofilament bundles.