Question

The giant protein titin maintains the organization of the ________ assisting in muscle stretching.

1) A band
2) I band
3) Z disc
4) M line

Answer 1

The giant protein titin maintains the organization of the I band assisting in muscle stretching. Titin functions as a molecular spring and extends from the Z discs to the M line of sarcomeres. It allows muscle contraction and relaxation.

Step-by-step explanation:

The giant protein titin maintains the organization of the I band assisting in muscle stretching. Titin functions as a molecular spring and extends from the Z discs to the M line of sarcomeres. It allows muscle contraction and relaxation. The giant protein titin maintains the organization of the I band assisting in muscle stretching.

One sarcomere, the functional unit of skeletal muscle, consists of an I band, an A band, and two Z discs. The Z disc marks the border of units called sarcomeres, while the I band is the space between two consecutive Z discs. Titin, the largest known polypeptide in muscle cells, extends from the Z discs to the M line of sarcomeres and functions as a molecular spring, allowing muscle contraction and relaxation.