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.
During exercise, your heart typically beats faster so that more blood gets out to your body. Your heart can also increase its stroke volume by pumping more forcefully or increasing the amount of blood that fills the left ventricle before it pumps.
Section 3.2Primary Structure: Amino Acids Are Linked by Peptide Bonds to Form Polypeptide Chains. Proteins are linear polymers formed by linking the α-carboxyl group of one amino acid to the α-amino group of another amino acid with a peptide bond (also called an amide bond).