CARBOHYDRATES:
Carbohydrates are defined as optically active polyhydroxy aldehydes or ketones or
the compound which produce such units on hydrolysis.
CLASSIFICATION OF CARBOHYDRATES;-
1.Monosaccharides
2.Oligosaccharides
MONOSACCHARIDES
The monosaccharides is also called simple sugar, compound which possesing free aldehyde
(-CHO) or ketone (-c=o) group and 2 or more (-OH) group. The genral formula of monosaccharides
is Cn(H2O)n.
| MONOSACCHARIDES | GENRAL FORMULA | ALDOSE SUGAR(-CHO) | KETOSE SUGAR(-C=O) |
| Triose | C3H6O3 | Glyceraldehyde | Dihydroxyacetone |
| Tetroses | C4H8O4 | Erythrose | Erythrulose |
| pentose | C5H10O5 | D-Ribose,D-Xylose | D-Ribulose,D-xylulose |
| Hexoses | C6H12O6 | D-Glucose,mannose,Galactose | Fructose |
| Heptoses | C7H14O7 | Glucoheptose | Sedoheptulose D-sedoheptulose |
OLIGOSACCHARIDES
It is a compound sugar which yields two to ten molecules of same or different monosaccharides on hydrolysis.
It means on hydrolysis it gives monosaccharides if it gives two monosaccharides is known as disaccharides, for example ; lactose,Maltose, sucrose etc. and on three then it will be Trisaccharides, as example raffinose, Rhamninose, etc.
And so on ; Tetrasaccharides- Stachyose, Scorodose
Pentasaccharides: Verbascose.
POLYSACCHARIDES
IT consist of repeat unit of monosaccharides or their derivatives held together by glycosidic bonds.
FUNCTION; it is structural and storage of energy.
Polysaccharides are linear or branched polymers.
The genral formula is( C6H10O5)x.
Types of polysaccharides-
1.Homopolysaccharides; on hydrolysis it gives only single types of monosaccharides. For example- starch, pectin, chitin, glycogen, dextrin
- Heteropolysaccharides-on hydrolysis it gives different types of monosaccharides or sugar or their derivatives.
For example; Heparin, chondroitin,keratan sulfate. +++