Biomolecules are the organic compounds which form the basis of life, i. e., they build up the living system and responsible for their growth and maintenance.
The sequence that relates biomolecules to living organism is
Biomolecules → Organelles → Cells → Tissues → Organs → Living organism.
Carbohydrates
Optically active polyhydroxy aldehydes( aldcses) or ketones( ketoses) or compounds which on hydrolysis give these units are known as carbohydrates. They are also called saccharides
( Latin Saccharum = sugar) due to sweet taste of simpler members.
Depending upon their behaviour towards hydrolysis, carbohydrates can be of following three types
Monosaccharides
These cannot be hydrolysed to simpler molecules and further subdivided into tetroses, pentoses or hexoses depending upon the number of carbon atoms. These are also called homopolysaccharides.
Aldotetroses Erythrose, Threose Aldopentoses Xylose, Ribose, Aldohexoses Glucose, Galactose, Ketohexoses Fructose
All naturally occurring monosaccharides belong to D-series.
killiani synthesis is used to convert an aldose into next higher aldose.