How do smooth muscle cells differ from striated cells with respect to the role of T-tubules, tropomyosin, and attachment of thin fibers?

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asked May 15, 2024 26.8k views

1 Answer

Rhesous · Answer 1 · 2024-05-22T09:52:45+0000

Smooth muscle cells differ from striated cells in terms of T-tubules, tropomyosin, and attachment of thin fibers.

Smooth muscle cells differ from striated cells in several aspects:

T-tubules: Smooth muscle cells do not have T-tubules like striated cells do. T-tubules are invaginations of the cell membrane that allow for the rapid spread of electrical signals in striated muscle cells.
Tropomyosin: Smooth muscle cells also differ in the arrangement of tropomyosin, which is a protein involved in muscle contraction. In striated cells, tropomyosin is arranged in a regular pattern, while in smooth muscle cells, it is scattered throughout the cell.
Attachment of thin fibers: In striated muscle cells, thin fibers (actin) are attached to a specialized structure called the Z-disc, which helps to organize the sarcomeres. In smooth muscle cells, thin fibers are attached to dense bodies, which are similar to Z-discs but dispersed throughout the cell.