Semantides are information-carrying molecules. Semantides provide taxonomic data not on the basis of presence or absence, but in terms of sequences, ratios or percentages,. Semantides are of three types, viz., Primary semantide – DNA Secondary semantide- RNA Tertiary semantides – Proteins Sometimes the semantides together with the larger polysachharides, are …

The chemical substances which have been found very useful in taxonomy are secondary metabolites. Secondary metabolites (secondary plant products) perform non-vital (or at least non- universally vital) functions, and are less widespread in plants. The restricted occurrence of these metabolites among plants renders them valuable as taxonomic information. Secondary plant …

Plant Chemotaxonomy is one of the more fashionable and rapidly extending areas of plant taxonomy that seeks to utilize chemical information to improve classification of plants.It has many diverse and indeed ancient origins. 1. The foremost comes the search by Herbalists, and latterly by pharmacists, for drugs, which has involved …