Marijuana, the most often used illegal drug in this country, is a product of the hemp plant, Cannabis sativa. The main active chemical in marijuana, also present in other forms of cannabis, is THC (delta-9-tetrahydrocannabinol). Of the roughly 400 chemicals found in the cannabis plant, THC affects the brain the most.
Cats 'vibrate' when marking territory-spayed cats can also 'dry' spray. Spayed male cats urine doesn't smell. They swish their tales as a sign of annoyance or anger. If the tip of the tail 'trembles', it's quite often a sign of being 'unsure' about something. Source(s): Cat owner.
Angry Cats. A cat flicking its tail usually means that the cat is slightly annoyed. It can indicate interest, but you'll be able to tell by its ears. If the cat is actually happy, its ears will be up and alert. Otherwise, big flicking motions show that the cat is annoyed.