Question

Which of the following carbohydrates is a trisaccharide carbohydrate?

• A. Raffinose
• B. Sucrose
• C. Starch
• D. Cellulose

Hint:

Carbohydrate classification:
Monosaccharide: Glucose, Fructose.
Disaccharide: Sucrose, Maltose, Lactose.
Trisaccharide: Raffinose.
Tetrasaccharide: Stachyose.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Carbohydrates are categorized based on degree of polymerization into monosaccharides (1 unit), disaccharides (2 units), trisaccharides (3 units), and polysaccharides ($> 10$ units).
Key Formula or Approach:
\[ \text{Raffinose } (\text{C}_{18}\text{H}_{32}\text{O}_{16}) + 2\text{H}_2\text{O} \longrightarrow \text{D-Galactose} + \text{D-Glucose} + \text{D-Fructose} \]

Step 2: Detailed Explanation:
Analyzing the carbohydrates:
1. Raffinose: A trisaccharide composed of three monosaccharide units (galactose, glucose, and fructose) linked by glycosidic bonds.
2. Sucrose: A disaccharide (glucose + fructose).
3. Starch & Cellulose: Homopolysaccharides composed of thousands of repeating D-glucose monomers.

Step 3: Final Answer:
Thus, the trisaccharide carbohydrate is Raffinose, corresponding to option (A).