The document discusses monosaccharides and polysaccharides, emphasizing their structures and biological functions. Monosaccharides, such as glucose and fructose, are simple sugars essential for energy production, while polysaccharides, including starch and glycogen, serve as storage forms of carbohydrates in plants and animals. Additionally, it highlights the roles of these carbohydrates in nature and mentions other polysaccharides like cellulose and chitin.

1. Monosaccharides and
Polysaccharides and its
Biological Functions
Presented by
Miss Pratiksha G Puranik
M.Sc.(Zoology),B.Ed., MH-SET

2. Contents
• Introduction
• Monosaccharide
• Biological Important
• Polysaccharide
• Biological Important
• Reference

3. Introduction
• Monosaccharide's are the simplest
carbohydrates they cannot be broken down
to the smaller carbohydrates.
• Polysaccharides are large molecules
containing 10 or more monosaccharide
units. Carbohydrate units are connected in
one continuous chain or the chain can be
branched.

4. Monosaccharide
• The monosaccharide is the simplest sugar.
• The monosaccharides are either aldehyde or
ketone with two or more hydroxyl groups.
e.g., glucose, fructose
• The six carbon monosaccharide glucose and
fructose have five hydroxyl groups.

5. The Two Families of
Monosaccharide Are Aldoses and
Ketones
• If the carboxyl group is at an end of the carbon
chain the monosaccharide is an aldose.
• If the carbonyl group is at any other position the
monosaccharide is a ketose.
• The simplest monosaccharides are the two three-
carbon trioses, glyceraldehydes an aldotriose, and
dihydroxyacetone, a ketoriose.

7. Biological Important
• Monosaccharide's are colorless, crystalline
solids.
• That are soluble in water but insoluble in
nonpolar solvents.
• Glucose is the most abundant
monosaccharide found in nature.
• Glucose is broken down in cells to produce
energy.
• Most have a sweet taste.
• Mannose, a monosaccharide, is found in
some fruits and vegetables.

8. Cont….
• Mannose is an epimer of glucose.
• Fructose is combined with glucose to give sucrose.
• Fructose is the sweetest monosaccharide and is found in fruits,
vegetables, and honey.

9. Polysaccharide
• Polysaccharide also called glycans.
• Homopolysaccharides contain only a single
monomeric species.
• Heteropolysaccharides contain two or more
different kinds.
e.g., starch, glycogen,dextrans

10. Starch and glycogen
• Starch contain two types of glucose polymer,
amylose and amylopectin.
• Glycogen is the main storage polysaccharide of
animal cells.

11. Fig:- Glycogen and Starch

12. Dextrans
• Dextrans are bacterial and yeast
polysaccharides made up of (α1-6) linked
poly-D-glucose all have
(α1-3) branches and some also have (α1-2)
or (α1-4) branches.

13. Biological Important
• Starch and glycogen are used for storage of
carbohydrates.
- starch is found in plants and glycogen in animals.
• Glucose is stored as glycogen in animals and starch
in plants.
• Glycogen is stored in:
• Liver
• Muscle cells

14. Cont….
• Dental plaque, formed by bacteria growing
on the surface of teeth, is rich in dextrans.
• Two important polysaccharides are cellulose
in plants and chitin in arthropods and fungi.

15. References
• Principles of Biochemistry (fifth edition)
David L. Nelson
Michael M. Cox

16. Thank You