1. Stanmore College Interview
Presentation
Introduction to Biological
Molecules
Lyndsae Drury Biology
Lecturer

2. Biological molecules
•
1. Water
•
2. ions
•
3. Sugars, Carbohydrates
•
4. Proteins
•
5. Lipids

5. Carbohydrates
Carbohydrates contain 3
elements:
•
Carbon (C)
•
Hydrogen (H)
•
Oxygen (O)

6. •
Carbohydrates are found in one of three
forms:
•
Monosaccharides
•
Disaccharides (both sugars)
•
Polysaccharides
•
Monosaccharides
•
General formula:.

7. •
Trioses: (e.g. glyceraldehydes), intermediates
in respiration and photosynthesis.
•
Tetroses: rare.
•
Pentoses: (e.g. ribose, ribulose), used in the
synthesis of nucleic acids (RNA and DNA), co-
enzymes (NAD, NADP, FAD) and ATP.
•
Hexoses: (e.g. glucose, fructose), used as a
source of energy in respiration and as building
blocks for larger molecules.
•
All but one carbon atom have an alcohol (OH)

10. •
Mono Saccharides

12. •
Examples of Disaccharides
•
Sucrose: glucose + fructose,
•
Lactose: glucose + galactose,
•
Maltose: glucose + glucose.
•
Maltose: glucose + glucose.

13. Disaccharides

14. Starch made of two polysaccharides

15. Differences between Glycogen and
Amylopectin polysaccharides.
The branches are formed by linking C # 1 to a C # 6 through an acetal
linkages. In glycogen, the branches occur at intervals of 8-10 glucose
units, while in amylopectin the branches are separated by 12-20
glucose units

18. Other Novel Polysaccharides
Chitin polysaccharide found
in crabs and sea shells
whereas Lignin in wood