Structural proteins that typically assemble into large cables or threads, to provide mechanical support to cells or organisms are classified as proteins.

Fibrous

Explanation:

Proteins are assembled according to their functions. Fibrous proteins usually provide protection and support to cells. They are made up of polypeptides that have elongated shape and assembles in large cables or threads. These proteins are differentiated from globular proteins by their globular form and repeated units of amino acids.

For example the fibrous proteins involved in horns, hair and nails is alpha-keratin.  Elastin found in skin and ligament is also a fibrous protein. Collagen includes collagen fibrils that have tensile strength of steel is also a fibrous protein found in cartilages and bones.

cuz they cant breath

explanation:

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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