1) Biomolecules
Biomolecules are organic compounds that are essential for structure & function of all living
organisms. They are building blocks of life & are primarily composed of Carbon (C), Hydrogen (H),
Oxygen (O) & Nitrogen, with some also containing Phosphorus (P) & Sulphur (S).
Biomolecules are divided into following groups according to the variability in structure & function:
1. Carbohydrates
2. Proteins
3. Lipids
4. Nucleic Acids
5. Conjugated Molecules
2) Major Classes of Biomolecules
Structure Elements Linkages Functions
n ring or linear chains & repeating units C, H, O Glycosidic bond Primary energy (short term), structural support in plants
Diverse, no single unit C, H, O (less O) Ester bond Long term energy source, insulation
near or double stranded form C, H, O, N, P Phosphoester bond Genetic information generation & duplication
Complex 3D structure C, H, O, N, sometimes S Peptide bond Enzyme, structure, movement, defense
3) Carbohydrates
Hydrated carbon i.e. water-containing carbon compounds. The carbon & hydrogen atoms are
present in the ratio of 2:1 as present in water.
General formula: Cn(H2O)n or CnH2nOn
According to IUPAC, carbohydrates are polyhydroxy carbonyl compounds.
→ Polyhydroxy = many –OH (alcohol) groups
→ Carbonyl group = C=O group
The characteristic carbonyl group is found in aldehydes & ketones.
→ Aldoses: monosaccharides have carbonyl group (CHO) at the end of the carbon chain.
→ Ketoses: carbon chain with CO at the middle.
Many carbohydrates are sweet in taste, that’s why they are called saccharum or saccharides.
Found in all organisms.
Play both structural & functional roles.
4) Classification of Carbohydrates
Carbohydrates → Monosaccharides → Oligosaccharides → Polysaccharides
Monosaccharides
• 'Mono' means 'one' & 'saccharide' means 'sugar'.
• A monosaccharide contains one sugar molecule.
• It is the simplest form of carbohydrate.
• Can’t break through hydrolysis.
• Act as fundamental building blocks for more complex carbohydrates like oligosaccharides &
polysaccharides.
• General empirical formula is Cn(H2O)n.
• Crystalline solids
• Sweet in taste
• Soluble in water
• Monosaccharides contain 3 to 10 carbon atoms.
• All monosaccharides are reducing sugars.
Biomolecules are organic compounds that are essential for structure & function of all living
organisms. They are building blocks of life & are primarily composed of Carbon (C), Hydrogen (H),
Oxygen (O) & Nitrogen, with some also containing Phosphorus (P) & Sulphur (S).
Biomolecules are divided into following groups according to the variability in structure & function:
1. Carbohydrates
2. Proteins
3. Lipids
4. Nucleic Acids
5. Conjugated Molecules
2) Major Classes of Biomolecules
Structure Elements Linkages Functions
n ring or linear chains & repeating units C, H, O Glycosidic bond Primary energy (short term), structural support in plants
Diverse, no single unit C, H, O (less O) Ester bond Long term energy source, insulation
near or double stranded form C, H, O, N, P Phosphoester bond Genetic information generation & duplication
Complex 3D structure C, H, O, N, sometimes S Peptide bond Enzyme, structure, movement, defense
3) Carbohydrates
Hydrated carbon i.e. water-containing carbon compounds. The carbon & hydrogen atoms are
present in the ratio of 2:1 as present in water.
General formula: Cn(H2O)n or CnH2nOn
According to IUPAC, carbohydrates are polyhydroxy carbonyl compounds.
→ Polyhydroxy = many –OH (alcohol) groups
→ Carbonyl group = C=O group
The characteristic carbonyl group is found in aldehydes & ketones.
→ Aldoses: monosaccharides have carbonyl group (CHO) at the end of the carbon chain.
→ Ketoses: carbon chain with CO at the middle.
Many carbohydrates are sweet in taste, that’s why they are called saccharum or saccharides.
Found in all organisms.
Play both structural & functional roles.
4) Classification of Carbohydrates
Carbohydrates → Monosaccharides → Oligosaccharides → Polysaccharides
Monosaccharides
• 'Mono' means 'one' & 'saccharide' means 'sugar'.
• A monosaccharide contains one sugar molecule.
• It is the simplest form of carbohydrate.
• Can’t break through hydrolysis.
• Act as fundamental building blocks for more complex carbohydrates like oligosaccharides &
polysaccharides.
• General empirical formula is Cn(H2O)n.
• Crystalline solids
• Sweet in taste
• Soluble in water
• Monosaccharides contain 3 to 10 carbon atoms.
• All monosaccharides are reducing sugars.
