Monosaccharides & Disaccharides: The Basics

Disaccharides form when two monosaccharides join together through dehydration synthesis.During this process, a water molecule is removed as the two sugars form a glycosidic bond.Let's look at three common disaccharides found in nature.Sucrose, commonly known as table sugar, consists of glucose and fructose joined together.Lactose, found in milk, is made up of glucose and galactose.Maltose, or malt sugar, consists of two glucose molecules bonded together.The glycosidic bond that forms between the two monosaccharides is created through a dehydration synthesis reaction.This reaction results in the formation of a larger sugar molecule and the release of one water molecule.When we consume complex sugars like disaccharides, our digestive system must break them down before they can be used.Special enzymes in our digestive tract are responsible for breaking down different types of disaccharides.Lactase breaks down lactose into its component parts: glucose and galactose.Similarly, sucrase breaks down sucrose into glucose and fructose.Once broken down, these simple sugars can be absorbed by cells through special transport proteins called GLUT transporters.These transporters specifically allow monosaccharides like glucose to enter the cell, where they can be used for energy.However, some people lack certain digestive enzymes, leading to sugar intolerances. For example, in lactose intolerance, the lack of lactase enzyme prevents proper lactose breakdown.Without lactase, undigested lactose remains in the digestive system, causing uncomfortable symptoms.