Our body is regulated by something called the "Endo Cannabinoid System" (ECS). This system uses Nero-Transmitter's that our body makes to do its signally, IE, talking to other parts of the system. If we are anything, we are first and foremost "systems within systems", do something in one and it affects something else. The Cannabis plant makes various molecular formula's that we call Phyto Cannabinoids. All of this is done in the glands of the plant, mostly in the cells of leafs. These Cellular Glands are called Trichrome's. This process of making these Complex Molecules in the Trichromes is called Bio Synthesis. The plant takes simple molecules and various enzymes to catalyze a series of chemical reactions to make these Complex Molecules. These bigger molecules are able to speak to our Endo Cannabinoid System on our behalf and help create a state of Homeostasis. The Cannabis plant truly is a Chemical Factory. There are 500 different chemical compounds synthesized inside of a Cannabis plant, many are Terpines and Terpaniods but 113 of these are Cannabinoids that have been identified, however most are in such small quantities they are difficult to isolate. Worthy to note that the the Cannabis plant always synthesizes and accumulates these various Cannabinoids in their acidic forms.
Inside of these Trichromes the plant will make Terpenes and Cannabinoids from the smaller building block molecules. For Cannabinoids this all starts with "Geranyl Pyrophosphate", the very same thing our body uses to make cholesterol, the Cannabis plant will use to make Phyto Cannabinoids. They are made from Geranyl Pyrophosphate using either Olivetolic Acid or Divarinic Acid, with these these two, the Cannabis plant will make Phyto Cannabinoids with two major classes of Cannabinoids. These are classified as being either Pentyl Cannabinoids or Propyl Cannabinoids.
Most everyone's heard of Pentyl-Cannabinoids, just not the term. These are all the Cannabinoids with a C5 side chain, meaning a 5 carbon tail.
These are by far the most common type of Cannabinoids. They include CBGa, CBG, THCa, THC, CBDa, CBD, CBCa and CBC. These all use Olivetic Acid with Geranyl Pyrophosphate in a process called Geranyl Transferase to make up the first of the Pentyl-Cannabinoids CBGa, also known as Cannabigerolic Acid. Its what we call the Precursor Cannabinoid, IE, the mother of all other Pentyl Cannabinoids.
The Precursor Cannabinoid
CBGa is the first Cannabinoid the Cannabis plant makes. As the plant is sitting out in the sun it heats up and the season begins to change. Both the heat and time will cause it to go through a natural process called De-Carboxylation, (loss of carbon dioxide) and the CBGa in the plant will slowly begin to lose CO2. As this is happening the CBGa will turn into CBG or Cannabigerol.
Now a process called Enzyme Synthase begins inside the plants Trichromes. THCa synthase (THCAS) will begin to convert the CBGa and CBG into THCa, TetrahydroCannabinol-acid.
This is happening also to make CBDa and CBCa, they each have their own (CBDAS) Cannabidiolic-acid synthase and (CBCAS) Cannabichromene-acid synthase which in each case is making up the non-activated Cannabinoids, CBDa and CBCa.
The Other Cannabinoids
The other class of Cannabinoids, the Propyl class, have ‘tails’ that are 3 carbon atoms in length but they tend to be much more rare. Durban Poison is one of the more well known strains that uses Divarinic Acid to make CBGVa, a few other strains of cannabis also produce these "Other Cannabinoids". These other Cannabinoids are made from Divarinic Acid and Geranyl Pyrophosphate, again through the process of Geranyl Transferase. Instead of producing CBG acid, these plants produce CBGVa, which will then be further synthesized into the cannabinoids CBDVa, THCVa, and/or CBCVa.
All of these Divarinic Acid producing varieties of cannabis seem to originate from India, Nepal and parts of Africa.
THCV is considered the sports car of Cannabinoids but not as much is known about these Propyl-Cannabinoids or their shared ancestry between the different species that produce this rare class of Cannabinoids. Other strains that produce these Propyl-Cannabinoids are Dougs Varin and Willie Nelson.