Define "triose", "tetrose", "pentose", and "hexose" and identify which of these is/are most abundant

Monosaccharides are the simplest form of carbohydrates that cannot be hydrolyzed to smaller compounds. Monosaccharides are the basic units of carbohydrates and are also known as simple sugars.  

The monosaccharides are classified on the basis of number of carbon atoms present.

Triose is a type of monosaccharide molecule, which is composed of 3 carbon atoms.

Tetrose is a type of monosaccharide molecule, which is composed of 4 carbon atoms.

Pentose is a type of monosaccharide molecule, which is composed of 5 carbon atoms.

Hexose is a type of monosaccharide molecule, which is composed of 6 carbon atoms.

D-glucose is a hexose sugar and it is the most abundant monosaccharide in the nature.

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