Question

Which of the following is an aldose sugar?

• A. Fructose
• B. Glucose
• C. Erythrulose
• D. Ribulose

Answer 1

The correct option is B Glucose

Monosaccharides are the simplest sugars which cannot be hydrolysed further. Monosaccharides can be divided further based on the number of carbon atoms present into trioses (3C) which include glyceraldehyde (aldose) and dihydroxyacetone (ketose), tetroses (4C) which include erythrose (aldose) and erythrulose (ketose), pentoses (5C) which include ribose (aldose), deoxyribose and ribulose (ketose), hexoses (6C) which include glucose (aldose), fructose (ketose), galactose, etc. If the structure contains a -CHO (aldehyde) group, it is referred to as aldose sugar and if it contains >C=O (keto) group, it is referred to as ketose sugar. Glucose has a terminal -CHO group in its structure, so it is an aldose sugar. Fructose, erythrulose and ribulose have a subterminal >C=O group in their structure, so they are ketosugars.


Glucose