ANS:B - disacchride

The correct answer is: disaccharide

Explanation:

Sucrose is a disaccharide composed of two monosaccharides: glucose and fructose, linked together by a glycosidic bond.

Explanation of Disaccharide

Disaccharides are carbohydrates composed of two monosaccharide units linked together by a glycosidic bond. Here are the key aspects:

1. Structure

• Composition: Disaccharides consist of two simple sugars (monosaccharides) joined together. This bond forms through a dehydration reaction, which involves the removal of a water molecule.
• Common Examples: Some well-known disaccharides include:
  • Sucrose: Composed of glucose and fructose (table sugar).
  • Lactose: Composed of glucose and galactose (milk sugar).
  • Maltose: Composed of two glucose molecules (malt sugar).

2. Formation and Breakdown

• Formation: Disaccharides are formed through condensation reactions where two monosaccharides combine, releasing water.
• Hydrolysis: Disaccharides can be broken down into their constituent monosaccharides through hydrolysis, which adds water and is often catalyzed by enzymes.

3. Functions and Roles

• Energy Source: Disaccharides serve as important sources of energy. When consumed, they are broken down into monosaccharides and utilized by the body.
• Taste and Sweetness: Many disaccharides, especially sucrose and lactose, contribute to the sweetness of foods.

4. Digestion and Absorption

• Digestive Enzymes: Specific enzymes are required to break down disaccharides into monosaccharides. For example, sucrase breaks down sucrose, lactase breaks down lactose, and maltase breaks down maltose.
• Absorption: Once digested into monosaccharides, they are absorbed into the bloodstream and transported to cells for energy.

Summary

Disaccharides are carbohydrates made up of two monosaccharide units linked by glycosidic bonds. They play essential roles in nutrition, energy provision, and food flavor, and are crucial in various biological processes.