Functions of Cannabinoids in Marijuana

As with virtually all other psychoactive compounds occurring in plants, the function of cannabinoids is unknown. In order to have evolved the many genes necessary for the synthesis of such complex molecules, they or their precursors probably serve an important purpose. This makes the failure to have a ready explanation for their presence all the more frustrating, especially in view of the tremendous advances in plant biochemistry. It seems likely that the cannabinoids are an important constituent of resin, which serves to protect the plant from patho- 

Humans have selected marijuana for perhaps 10,000 years for use as fiber, food and medicine. The varieties producing much resin have been carefully bred and widely distributed, and this characteristic is probably much more prominent than in ancestral hemp populations. Thus, the abundance of cannabinoids in marijuana may be due to selecrion by our ancestors. 

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