eng Science and Education Publishing Journal of Polymer and Biopolymer Physics Chemistry 2373-3411 2018-11-21 6 1 39 44 10.12691/jpbpc-6-1-5 JPBPC2018615 article Mohammad R. Kasaai reza_kasaai@hotmail.com 1 Department of Food Science and Technology, Sari Agricultural Sciences and Natural Resources University, Khazar Abad road, Km. 9, P.O. Box, 578, Sari, Mazandaran, Iran In this study, molecular weight distribution (MWD), of polymers with emphasis on MWD of biopolymers, e.g, carbohydrate polymers, proteins, deoxyribonucleic acid, DNA, and ribonucleic acid, RNA, are reviewed. The MWD of biopolymers are compared with those of synthetic polymers. The constitution of a polymer as well as the MWD may be described either by a set of different average molecular weights, the ratios of two different types of average molecular weights, or by the distribution functions via graphical presentation. Polysaccharides in a similar way to synthetic polymers are polydisperse polymers, whereas proteins, DNA, and RNA, are mostly monodisperse macromolecules. http://pubs.sciepub.com/jpbpc/6/1/5/jpbpc-6-1-5.pdf biopolymers molecular weight distribution proteins polysaccharides DNA RNA