Define Protein Hormone and Steroid Hormone

Further, hormones are of two different chemical types - protein hormone and steroid hormone. Most of the hormones belong to the category of small proteins or derivatives of proteins such as polypeptides, polypeptide amines or chemical compounds derived from one or more amino acids. The adrenocortical and sex hormones are steroid hormones. They have a chemical structure similar to that of cholesterol. Next, let us learn how do these hormones act or function i.e. the mechanism of hormone action.