Problem 43 - Anatomy and Physiology of Animals

Question

If the disaccharide maltose is formed from two glucose monosaccharides, which are hexose sugars, how many atoms of carbon, hydrogen, and oxygen does maltose contain and why?

Step-by-Step Solution

Answer

Maltose contains 12 carbon, 22 hydrogen, and 11 oxygen atoms.

Step 1: Identify the Chemical Formula for Glucose

Each glucose molecule is a hexose sugar, which means it contains 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms. Therefore, the chemical formula for glucose is \(C_6H_{12}O_6\).

Step 2: Combine Two Glucose Molecules

To form maltose, you need to join two glucose molecules. If no atoms were lost during this combination, the formula would be \((C_6H_{12}O_6)_2\), or \(C_{12}H_{24}O_{12}\).

Step 3: Account for Water Loss During Glycosidic Linkage

When two glucose molecules combine to form maltose, a dehydration synthesis reaction occurs. During this reaction, a water molecule \((H_2O)\) is removed. Thus, the formula of maltose is \(C_{12}H_{22}O_{11}\), because \(H_2O\) (\(2H\) and \(1O\)) is subtracted from the initial sum.

Key Concepts

Glucose Monosaccharides

Glucose is a fundamental sugar molecule critical to many biological processes. It is a type of simple sugar known as a monosaccharide. Monosaccharides are the most basic form of carbohydrates, consisting of a single sugar molecule.

Glucose is the primary source of energy in most living organisms. It circulates in the bloodstream and provides fuel for cellular activities. As a monosaccharide, glucose is a building block for more complex sugars, such as disaccharides and polysaccharides.

• Monosaccharides: Single sugar molecules.
• Glucose: Essential energy source for cells.
• Building Blocks: Foundation for complex sugars.

Hexose Sugars

Hexose sugars are a group of monosaccharides containing six carbon atoms. The term 'hexose' comes from the Greek word for six, indicating the number of carbon atoms present. Glucose is a type of hexose sugar, as are fructose and galactose.

These sugars play a crucial role in biochemistry. The six-carbon structure of hexose sugars makes them versatile for forming larger carbohydrate molecules. Hexoses can form complex structures through processes such as glycosidic linkages, which involve bonding between sugar molecules.

• Hexose: Six carbon sugar.
• Glucose and Fructose: Examples of hexose sugars.
• Complex Formation: Building larger carbohydrates.

Disaccharides

Disaccharides are sugars formed by the combination of two monosaccharide molecules. They are more complex than monosaccharides but simpler than polysaccharides. When two glucose molecules link together, they form the disaccharide known as maltose.

The process of forming a disaccharide involves a dehydration synthesis reaction, also called a condensation reaction. In this process, a molecule of water is removed as the monosaccharides bond. Maltose, lactose, and sucrose are common disaccharides important in nutrition and metabolism.

• Formation: Two monosaccharides bond.
• Water Loss: Dehydration synthesis reaction.
• Maltose: Formed from two glucose molecules.

Chemical Formula

Understanding chemical formulas is crucial for deciphering the structure of molecules. The chemical formula of glucose is represented as \(C_6H_{12}O_6\). This indicates each glucose molecule contains six carbon atoms, twelve hydrogen atoms, and six oxygen atoms.

When forming maltose, two glucose molecules undergo dehydration, losing one water molecule. This causes the resulting chemical formula for maltose to be \(C_{12}H_{22}O_{11}\), rather than the initial combination of \(C_{12}H_{24}O_{12}\). Recognizing chemical formulas helps in understanding the transformations that occur during chemical reactions.

• Glucose Formula: \(C_6H_{12}O_6\).
• Maltose Formation: Involves water loss.
• Resulting Formula: \(C_{12}H_{22}O_{11}\).