解释为什么蛋白质是聚合物,而脂质不是聚合物.Explain why proteins are considered polymers but lipids are not.最好用英文回答.用英文回答,而且是正确答案者,

A polymer is a large molecule (macromolecule) composed of repeating structural units typically connected by covalent chemical bonds.Proteins (also known as polypeptides) are organic compounds made of ...