Title: 
Headings: 

Content: They transmit electrical impulses from one muscle cell to another. This way, only some muscle cells need to be activated by a nerve--the rest will be signaled through the T-tubule network, so that all of the muscle cells will contract together. So what happens when you block the T-tubules? Your muscle doesn't work so well anymore. You might still get cell-to-cell communication (I'm not sure), but even if you did, it would be slow so that the muscle fibers would not contract synchronously. Addendum: It's been 6 or 7 years since I last studied physiology, so I think you should listen to the professor, not me! 10
Anonymous
2 decades ago
The t-tubules spread the action potential across the muscle cell and down into it. Once the action potential travels down the t-tubule it stimulates the terminal cisternae to release calcium ions which bind to the the troponin which changes shape moving the tropomyosin away from the myosin binding sites on the actin. This allows actin and myosin to bind and the muscle to contract.