In medical specialty, biological activity or medicine activity describes the helpful or adverse effects of a drug on living matter. once a drug could be an advanced chemical mixture, this activity is exerted by the substance's active ingredient or pharmacophore however are often changed by the opposite constituents. The medicine activity medicine of medicine of medication depends on however the drugs act with proteins, enzymes, receptors, macromolecule, or bio membranes. Figure 4.19 illustrates the interaction between a stereo isomeric drug and biological receptors. The left structure fits well compared with the proper one, therefore the left one is biologically active and therefore the right one is biologically inactive due to the couple with biological receptors
