[Solved] Structure F on the skin diagram is a(n) A) oil gland. B) sweat gland. C) sensory receptor. D) wax gland. E) naked nerve ending. Cravings: Intense desires or urges for specific substances or experiences, often associated with addiction. Addictive Substance: A chemical or compound that causes a compulsive, and often harmful, need for repeated consumption. Opiates: A group of drugs derived from opium used for their analgesic, sedative, and euphoric effects; includes both natural and synthetic compounds. Type I Alcoholism: A subtype of alcoholism characterized by early onset, often with a genetic component, and is associated with rapid progression of dependence.