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Carbohydrates – Classification (aldoses and ketoses), monosaccahrides (glucose and fructose), D-L configuration oligosaccharides (sucrose, lactose, maltose), polysaccharides (starch, cellulose, glycogen) importance.

Proteins – Elementary idea of α – amino acids, peptide bond, polypeptides, proteins, structure of proteins – primary, secondary, tertiary structure and quaternary structures (qualitative idea only), denaturation of proteins; enzymes. Hormones – Elementary idea excluding structure.

Vitamins – Classification and functions.

Nucleic Acids: DNA and RNA.

chemistry 12th class cbse notes

Nucleic Acids

Nucleic Acids Nucleic acids are chain like polymers of thousands of nucleotide units, hence they are also called polynucleotides. These are mainly of two types, the...
chemistry 12th class cbse notes


Vitamins Vitamins are a group of organic compounds which are essential for normal growth and nutrition and are required in very...
chemistry 12th class cbse notes


Enzymes Enzymes are biological catalysts. Chemically all enzymes are globular proteins. Being proteins, they have colloidal nature and...
chemistry 12th class cbse notes


Proteins The word protein is derived from Greek word, “proteios” which means primary or of prime importance. All proteins are polymers of -amino acids. Amino Acids The...
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Starch, Cellulose & Glycogen

Polysaccharides Polysaccharides contain a large number of monosaccharide units joined together by glycosidic linkages. They mainly act as the food storage or structural materials. Starch ...
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Sucrose, Maltose & Lactose

Disaccharides: The two monosaccharides are joined together by an oxide linkage formed by the loss of a water molecule. Such a linkage between two monosaccharide...
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Fructose (Ketohexose)

Fructose (Ketohexose) Fructose is an important ketohexose. It is obtained along with glucose by the hydrolysis of disaccharide, sucrose. Fructose also has the molecular formula C6H12O6. The...
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Glucose is a monosaccharide’s with molecular formula C6H12O6. It is present in sweet fruits and in honey. Preparation of Glucose: #1 Preparation of Glucose From sucrose, C12H22O11: #2 Preparation of Glucose From starch C6H10O5: Structure...
chemistry 12th class cbse notes

Biomolecules and Carbohydrates

Biomolecules Biomolecules are the organic molecules that are involved in the maintenance and metabolic processes of living organisms. Thus, they build up the living system...