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Biomolecules — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryBiomolecules4 Marks
Question
Describe detailed information on classification of carbohydrates.
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Answer

→Carbohydrates are classified on the basis of their behaviour on hydrolysis. They have been broadly divided into following 3 groups
(i) Monosaccharide compounds :
→"A carbohydrate that can not be hydrolysed further to give simpler unit of polyhydroxy aldehyde or ketone is called a monosaccharide."
→About 20 monosaccharides are known to occur in nature. Some common examples are glucose, fructose, ribose, etc.
(ii) Oligosaccharide compounds :
→"Carbohydrates that yield two to ten monosaccharide units, on hydrolysis are called oligosaccharides."
→They are further classified as disaccharides, trisaccharides, tetrasaccharides, etc., depending upon the number of monosaccharides they provide on hydrolysis.
→Amongst these the most common are disaccharides. The two monosaccharide units obtained on hydrolysis of a disaccharide may be same or different.
→For example, one molecule of sucrose on hydrolysis gives one molecule of glucose and one molecule of fructose where as maltose gives two molecules of only glucose.
(iii) Polysaccharide compounds:
→"Carbohydrate which yield a large number of monosaccharide units on hydrolysis are called polysaccharides."
→Some common examples are starch, cellulose, glycogen, gums etc. Polysaccharides are not sweet in taste. Hence, they are also called non- sugars.

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