Question

Identify the disaccharide that fits each of the following descriptions: a. ordinary table sugar b. found in milk and milk products c. also called malt sugar d. hydrolysis gives galactose and glucose

Short answer

a. Sucrose; b. Lactose; c. Maltose; d. Lactose

Step-by-step solution

Identify Ordinary Table Sugar

Ordinary table sugar is commonly known as sucrose. It is a disaccharide composed of glucose and fructose.

Identify Disaccharide Found in Milk and Milk Products

The disaccharide found in milk and milk products is lactose. Lactose consists of glucose and galactose.

Identify Malt Sugar

Malt sugar, also known as maltose, is another type of disaccharide. It is made up of two glucose molecules.

Identify Disaccharide that Hydrolyzes into Galactose and Glucose

A disaccharide that hydrolyzes to produce galactose and glucose is lactose.

Key concepts

Sucrose

Sucrose, also known as ordinary table sugar, is one of the most common disaccharides. It is composed of two monosaccharides: glucose and fructose. This combination makes sucrose a quick source of energy.

When you ingest sucrose, your body breaks it down through a process called hydrolysis. During hydrolysis, enzymes in your digestive system split sucrose into its individual glucose and fructose units. These simple sugars are then absorbed into your bloodstream, providing fuel for your cells.

It's interesting to note that sucrose is naturally found in many plants, particularly in sugarcane and sugar beets. These plants are harvested and processed to produce the white granulated sugar you use in cooking and sweetening beverages.

Lactose

Lactose is a disaccharide found predominantly in milk and dairy products. It consists of two simpler sugars: glucose and galactose. Lactose is often referred to as milk sugar due to its presence in milk.

In the digestive process, lactose undergoes hydrolysis, splitting into glucose and galactose. This reaction is facilitated by the enzyme lactase. People who produce enough lactase can easily digest dairy products. However, lactose intolerance occurs when individuals lack sufficient lactase, resulting in digestive discomfort after consuming dairy.

Lactose is not only essential for infants, who consume it through breast milk, but also for understanding various dairy-related digestive issues.

Maltose

Maltose, commonly referred to as malt sugar, is another disaccharide crucial in biochemistry. It is composed of two glucose molecules linked together.

Maltose is formed during the breakdown of starches, such as those found in grains. For example, when you chew starchy foods like bread or potatoes, enzymes begin converting the starch into maltose.

This disaccharide is significant in brewing and fermentation processes. During these processes, maltose is further broken down into glucose, which is then fermented by yeast to produce alcohol and carbon dioxide. Consequently, maltose plays a pivotal role in the production of beer and other fermented beverages.

Hydrolysis

Hydrolysis is a fundamental biochemical reaction involving the breakdown of compounds through the addition of water. When it comes to disaccharides like sucrose, lactose, and maltose, hydrolysis is the mechanism by which they are decomposed into their constituent monosaccharides.

For instance, during sucrose hydrolysis, water is added to break the bond between glucose and fructose. Similarly, lactose is hydrolyzed into glucose and galactose under the action of water and specific enzymes. This reaction is crucial for nutrient absorption as it transforms complex sugars into simpler forms your body can easily absorb and utilize.

Hydrolysis is not limited to digestive processes, it also occurs in various metabolic pathways, contributing to the body's overall energy management and nutrient utilization.