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Biomolecules — Chemistry STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceChemistryBiomolecules3 Marks
Question
What are Carbohydrates? How are they classified?
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Answer

Carbohydrates are polyhydroxy aldox or ketose which on hydrolysis gives monomer of glucose or fructose.
Depending upon the reaction of carbohydrates with water, they can be classified into :
(i) Monosaccharides : These cannot be hydrolysed. They contain aldehyde or ketone as the principal functional group.
Examples : glucose, fructose.
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(ii) Disaccharides : Disaccharides on hydrolysis gives two monosaccharide molecules e.g., sucrose, lactose and maltose etc.
(iii) Polysaccharides : These are high molecular mass carbohydrates which on hydrolysis yield very large number of monosaccharides, e.g., starch and cellulose etc.

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