The photo is a colored scanning electron microscope photograph of the surface a young medical cannabis leaf. The leaf surface is covered with two types of specialised outgrowths designed to reduce the plant's palatability to animals. The pointed protuberances are cystoliths containing tough crystals of the mineral calcium carbonate. The rounded structures are glandular trichomes containing delta-9-tetrahydrocannabinol (THC) resin. THC is an active ingredient in medical cannabis and related products (hashish, edibles, drinks, tinctures, liniments, etc.).