Abstract
It has been shown by starch-gel electrophoresis that no marked changes take place in types of protein components present in extracts of endosperm between the 12th day after flowering and maturity. Excised wheat heads at about 20 days after flowering rapidly take up and incorporate radioactivity from [35S]sulphate and [14C]glycine into endosperm proteins. 'I'he changes and distribution of radioactivity between different groups of proteins has been followed from 1�5 to 48 hI after exposure to the radioisotope. The significance of the findings are discussed.