The term "pharmacologically active substance" is any chemical or substance that affects the physiology, the function of the body of a human or animal. These substances can be artificial or natural, i.e. those created by the body in response to stimulation or injury.
This term is frequently used to specify chemicals within a derivative (from a plant or animal source), those that actively affect a part of the body or its activities. It has also been used specifically to describe the alkaloid nicotine in proposals to restrict smoking.
Pharmacologically active natural products are frequently toxins and antifeedants to discourage predation. The alkaloids are bitter-tasting, the sesquiterpenes where you find feverfew and quinone, the alcohols such as ethanol and lactones are all classes of pharmacologically active naturals.
Purity: is the percentage of a drug without its degradation products or impurities or isomeric forms. The isomeric forms may be pharamlogically active, but in case of determination, isomeric forms will not be considered. Potency: is the measurement of a drug how potent it is. In this case the amount of drug may consider the pharmacologically active forms and impurities.
penicillin
To be active and healthy.
No a mixture is by definition not a pure substance.
Every drug has two components, one is the main substance which is the active pharmaceutical ingredient and the other is the inert substance, which can be the solvent in which the active ingredient is suspended.
kelvin
That's the definition of the density of the substance.
chemical change is the change of one substance into another substance.
Active transport is the movement of a substance against its concentration energy.
the hotness or coldness of a substance
Competitive Inhibition is a substance that binds to the active site in place of the substance while Non-competitive Inhibition is a substance that binds to a location remote from the active site. (: