On hydrolysis, which of the following carbohydrates gives only glucose ?
Show Hint
- Starch
- Sucrose
- Lactose
- Galactose
The Correct Option is A
Solution and Explanation
Step 1: Analyze starch. Starch is a polysaccharide made entirely of glucose units. Hydrolysis of starch produces: Glucose only
Step 2: Analyze sucrose. Sucrose consists of: Glucose + Fructose Hence hydrolysis does not produce only glucose.
Step 3: Analyze lactose. Lactose consists of: Glucose + Galactose Therefore hydrolysis yields two different monosaccharides.
Step 4: Analyze galactose. Galactose itself is a monosaccharide. It cannot hydrolyze further to produce glucose.
Step 5: Final conclusion. Only starch yields glucose as the sole hydrolysis product. \[ \boxed{\text{Starch}} \] Hence option (A) is correct.
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