What is the disaccharide often referred to as milk sugar?

Lactose is the correct answer as it is the disaccharide commonly known as milk sugar. It is composed of two simple sugars: glucose and galactose. This sugar is found predominantly in milk and dairy products, where it plays a vital role in providing energy as a carbohydrate source. Lactose is unique in that many individuals have varying levels of lactose intolerance, which means they may have difficulty digesting it due to the insufficient production of lactase, the enzyme responsible for breaking it down.

In contrast, sucrose is commonly known as table sugar and is composed of glucose and fructose, while glucose is a monosaccharide, the simplest form of sugar. Maltose, another disaccharide, is made up of two glucose molecules and is commonly found in malted foods and beverages and during the digestion of starch. Understanding these distinctions is important in the study of carbohydrates and their roles in nutrition.