Cannabis is part of the flowering plant family Cannabaceae originating within the temperate regions of the Northern Hemisphere and then spread worldwide. Cannabaceae are often dioecious (distinct male and female plants). The flowers are radially symmetrical without petals as these plants are pollinated by male plant pollen carried by the wind. As an adaptation to this kind of pollination, the reproductive calyx and corolla parts of the flower are reduced to only very small remnants found as a non-reproductive coating of the seed. Flowers are grouped to form clusters. In the dioecious plants the masculine flowers bracts are long and look like loose clusters while the feminine are shorter and bear fewer flowers.
Cannabis sativa subsp. sativa is the fiber type of cannabis mainly producing cannabidiol (CBD) with less than one percent of tetrahydrocannabinol (THC). The legality of hemp varies widely among countries. In Thailand, the governments regulate the concentration of THC and permit only hemp that is bred with an especially low THC content (not more than 0.2%) into commercial production. Meanwhile, Cannabis indica subsp. (or simply indica) is the drug-rich cannabis, whose THC contained within the upper part of the plant is above one percent. The higher concentrations of THC from smoking, vaporizing, within food, or as an extract provide euphoric effects making it popular for use both as a recreational and alternative medicine.
Cannabis is a truly multipurpose plant since its extraordinarily strong fibers have been used to make hemp cloth and paper for thousands of years having increased and longer-lasting strength than cotton. Cannabis also has a potential as a food source, for example, cannabis seed (hemp seed) which is exceptionally rich in polyunsaturated fats, essential fatty acids, and proteins. Moreover, cannabis has long been used for medicinal purposes which refers to the use of the constituent cannabinoids to treat disease or improve symptoms.
Cannabis is used to reduce nausea and vomiting during chemotherapy, to improve appetite in people with HIV/AIDS, and to treat chronic pain and muscle spasms. The cannabis resin utility as a drug, owing to its cannabinoid and terpene content, both for medical and psychoactive use has encouraged breeding that favor the plant’s production of resin. Breeding for increased drug production has produced a range of cannabis drug chemotypes regionally around the globe with more cultivars producing only THC, a few cultivars producing THC and CBD, even producing large amounts of CBD alone, and small number of cultivars primarily expressing cannabigerol (CBG), cannabichromene (CBC), or the propyl variants THCV and CBDV.
The cannabis produces more than 700 different chemical compounds including over 80 chemical alkaloids known as cannabinoids in which the cannabis “potency” is normally reserved for the quantitation of the major cannabinoids, principally THCA, THC, CBDA, CBD, and cannabinol (CBN). Cannabinoids, medicinally active substances produced within the plant, interact with the protein receptors of the body’s endocannabinoid system, located throughout the body. Different varieties of cannabis express different chemistries which in turn produce a varying range of medicinal effects and even different psychoactive trajectories.
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