327 - 11th Botany Textbook Volume 1

Monosaccharides
(simple sugars)
Carbohydrates
(Saccharides or sugars)
Oligosaccharides
( 2 to 10 sugar units)
Polysaccharides
( more than10 sugar units)
Functional
group
Number of
carbon atoms
Di - Tri - Tetra - Penta -
saccharides saccharides saccharides saccharides
Homo
polysaccharides
Hetero
polysaccharides
Aldoses
Glucose
Trioses
Glyceraldehyde
Maltose Raffinose Stachyose Verbascose Starch
Peptidoglycan
Ketose
Fructose
Tetroses
Erythrose
Lactose
Glycogen
Hyaluronic acid
Pentoses
Ribose
Hexose
Glucose
Sucrose Cellulose Chondroitin
sulphate
Chitin
Inulin
Keratan sulphate
Agar agar
8.3.1 Monosaccharides – The Simple
Sugars
Monosaccharides are relatively small
molecules constituting single sugar
unit. Glucose has a chemical formula of
C 6 H 12 O 6 . It is a six carbon molecule and
hence is called as hexose (Figure 8.6).
All monosaccharides contain one
of two functional groups. Some are
aldehydes, like glucose and are referred as
aldoses; other are ketones, like fructose
and are referred as ketoses.
Glucose is one of the
most well-known
molecules due to its
nature as an essential
nutrient for human
health. You ingest glucose in your
food, and then your body uses blood
to carry the glucose to the cells of
every organ for the purpose of energy
production.
Figure 8.6: Structure of Glucose
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