Vitamins may be regarded as organic compounds required in the diet in small amounts to perform specific biological functions for normal maintenance of optimum growth and health of the organism. Vitamins are classified as either water-soluble or fat soluble. There are 13 Vitamins necessary for human body.

Amino Acids

Amino acids are amphoteric electrolytes (also called as ampholytes) and can act as both acid (proton donor) and base (proton acceptor). They are joined together by condensation reaction between amino group of one acid and carboxyl group of another. Bond formed between two amino acids is known as peptide bond. Amino acids combine through peptide bond formation to form proteins, building blocks of life.

Enzymes (Nomenclature)

During early days, enzymes were given names by their discoverers in an arbitrary manner e.g. the names pepsin, trypsin and chymotrypsin convey no information about function of an enzyme or nature of substrate on which they act. Sometimes, suffix “ase” was added to the substrate for naming enzymes.

The International Union of Biochemistry (I.U.B.) initiated standards of enzyme nomenclature which recommend that enzyme names indicate both the substrate acted upon and type of reaction catalyzed.

Enzymes (Working Mechanism)

Enzymes are specialized protein complexes that serves as catalysts and accelerate the rate of reactions.

Enzymes vary in their specificity. While there are some enzymes that are only compatible with a single substrate, there are other enzymes that are compatible with several substrates, such as those with similar side chains, positions on a chain, or functional groups.
The working mechanism of enzymatic action  are described by two hypothesis which are: Lock and Key Hypothesis and Induced Fit Hypothesis.