Cannabis is one of humanity's oldest cultivated plants — and one of the most strongly distorted by political history. What has emerged over decades through prohibition and counter-propaganda is a mixture of myth, misinterpretation and genuine pharmacological knowledge that is barely separable any longer.
This article takes a step back: what is cannabis botanically? What does the plant contain? How do these compounds act? Without judgement, without agenda — only the factual basis.
Cannabis — the plant botanically
Cannabis is an annual, dioecious (separate male and female plants) herbaceous plant of the Cannabaceae family. Three subspecies are distinguished: Cannabis sativa (equatorial, adapted to long seasons), Cannabis indica (Central Asian, short season) and Cannabis ruderalis (northern, autoflowering).
The plant relevant for growing is female: female cannabis plants form resin-rich inflorescences (buds) in which most cannabinoids are concentrated. Male plants produce pollen, little resin, and are unwanted for the home grower without breeding interest.
The resin composition — trichomes — are specialised glandular hairs on flowers and leaves. They produce cannabinoids and terpenes as secondary plant compounds. The biological function: UV protection, protection against herbivores, possibly thermoregulation.
Cannabinoids — the pharmacologically active compounds
Cannabinoids are terpenoid compounds that occur specifically in cannabis. The plant produces over 100 different cannabinoids, of which about a dozen are well studied pharmacologically.
| Cannabinoid | Form in plant | Form after decarboxylation | Main effect (simplified) |
|---|---|---|---|
| THC | THCA (inactive) | THC (active) | Psychoactive, analgesic, appetite-stimulating |
| CBD | CBDA (inactive) | CBD (active) | Non-psychoactive, anxiolytic, antiepileptic |
| CBG | CBGA (precursor) | CBG | Antibacterial, neuroprotective (research phase) |
| CBN | THC degradation product | CBN | Mildly sedating, formed by THC oxidation |
| THCV | THCVA | THCV | Appetite-suppressing, antiepileptic (research phase) |
Decarboxylation: in the raw plant, cannabinoids exist as acid forms (THCA, CBDA) — these are not psychoactive. Only through heat (smoking, vaporising, baking) or UV light over time is the carboxyl group split off (decarboxylation), forming the active compounds. Fresh cannabis contains no THC — but rather THCA.
The endocannabinoid system — why cannabinoids work
Plant cannabinoids work in the human body because there is an endogenous (body-own) cannabinoid system: the endocannabinoid system (ECS). The ECS consists of cannabinoid receptors (CB1, CB2), endogenous ligands (anandamide, 2-AG) and enzymes for synthesis and breakdown.
CB1 receptors are mainly found in the central nervous system — that explains the psychoactive effects of THC (which binds to CB1). CB2 receptors are more strongly distributed in the immune system — relevant for the anti-inflammatory effects of CBD and other cannabinoids.
The ECS regulates physiological processes such as pain perception, mood, memory, appetite, immune response and sleep. It is not "optimised" for cannabis — cannabinoids happen to resemble endogenous signal molecules structurally enough to bind to the receptors.
Terpenes — aroma and more
Terpenes are aromatic compounds that occur in many plants — limonene in citrus, linalool in lavender, pinene in pines. Cannabis produces over 200 different terpenes. They are responsible for the characteristic smell of each strain.
Beyond the smell function, there are indications of pharmacological activity of the terpenes themselves — and of synergistic interactions between terpenes and cannabinoids (the so-called "entourage effect"). The research is, however, still thin: many of the circulating statements about specific terpene effects are not sufficiently substantiated by clinical studies.
| Terpene | Aroma | Also in | Research notes |
|---|---|---|---|
| Myrcene | Earthy, musky | Hops, mango | Sedating in high doses (animal studies) |
| Limonene | Citrus | Citrus peels | Anxiolytic (limited evidence) |
| Pinene | Pine, fresh | Pine needles, rosemary | Bronchodilating, anti-inflammatory |
| Linalool | Lavender, floral | Lavender | Anxiolytic, sedating (animal studies) |
| Caryophyllene | Peppery, spicy | Black pepper | Only terpene that binds directly to CB2 |
| Terpinolene | Fruity, resinous | Apples, lilac | Antioxidant (in vitro) |
Why the grow influences terpene composition
Terpenes are volatile compounds — they evaporate at high temperatures and are degraded by UV light. This has direct consequences for the grow: lamp distance, drying temperature and storage conditions influence the final terpene profile.
Genetics determines the terpene profile frame. Environmental conditions determine how that frame is filled. Two identical clones under different conditions can produce measurably different terpene profiles — that is not a myth but quantifiable in laboratory analyses.