Answer:
e. serving as cofactors for enzymes
Step-by-step explanation:
Proteins are substances formed by a set of amino acids linked together by peptide bonds. These substances perform the most diverse functions in the body, including participating in the composition of cells. There is no biological process in which a protein is not involved.
Proteins do not serve as enzyme cofactors, but their functions include maintaining blood viscosity and osmolarity, muscle contraction, catalytic enzyme reactions, and blood lipid transport. In addition, proteins can act as enzymes, participate in muscle contraction and hormone production, transport oxygen, produce antibodies, among other functions.