Proteins are of three types based on structure.
(i) Fibrous protein: Proteins with long and parallel polypeptide chains are fibrous proteins
says For example, collagen, elastin, keratin, fibrin etc.
(ii) Globular protein: Globular protein is called globular protein. Eg- serum, globulin, insulin, myoglobin, hemoglobin, alkaline phosphatase, cytochrome-c etc.
(iii) Intermediate protein: Fibrous protein is called intermediate protein. For example, fibrinogen.