On hydrolysis, which of the following carbohydrates gives only $\mathrm{\beta}$-glucose ?
Show Hint
- Starch
- Sucrose
- Maltose
- Cellulose
The Correct Option is D
Solution and Explanation
Step 1: How cellulose is built
Cellulose is a long straight chain made completely of β-D-glucose units, joined together by β(1→4) linkages.
Step 2: Break it with water
When these β-linkages are hydrolysed, every unit that comes out is β-D-glucose, and nothing else.
Step 3: Rule out the rest
Starch and maltose are built from α-glucose, so they give α-glucose. Sucrose gives a mix of glucose and fructose. So only cellulose gives pure β-glucose.
Answer: Option (D), Cellulose.
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