Question

part d (4 of 4)
what type of linkage occurs between the two monomers in this model of lactose?
β - 5,6 - glycosidic linkage
β - 4,1 - glycosidic linkage
β - 1,4 - glycosidic linkage
α - 1,4 - glycosidic linkage

Explanation:

Lactose is a disaccharide composed of galactose and glucose. The linkage between the two monomers in lactose is a $\beta$-1,4 - glycosidic linkage. This is because the anomeric carbon (carbon 1) of galactose in the $\beta$-configuration forms a glycosidic bond with the hydroxyl group on carbon 4 of glucose.

Answer:

$\beta$-1,4 - glycosidic linkage