Answer:
β-D-galactopyranosyl-(1→4) -α-D-glucopyranose.
Explanation:
Disaccharide alpha lactose is basically a molecule that contains two sugars, galactose and glucose. It is commonly present in the milk of cow and humans. It has alot of importance in pharmaceutical industry because it is used for formulation of different medicines. It is also used a s a nutrient because of the great proportion of sugar content.
It also plays an important role in the process of lactation in humans upon the birth of new born babies. It helps in osmotic regulation of several enzymes in new born babies and is digested by an enzyme called lactase. However, with the passage of time, activity of enzyme lactase slowly lowers in humans due to which they become lactose intolerant. Lactose intolerance results in poor digestion and abdominal pain in men. However, lactose is a potential nutrient component and pre-biotic for humans.
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