Like Y-DNA STRs, autosomal STRs are counts of repeated genetic code. As autosomal DNA recombines each generation, the number of markers shared with a specific ancestor is reduced by half each generation.
Heroin acts as a lipid soluble âprodrugâ within the brain, meaning that heroin itself is inactive but it is metabolized into an active form within the body. After crossing the blood-brain barrier, heroin is metabolized into morphine, which actively binds to opiate receptors in the brain producing the high.
1 Heroin is a highly addictive and rapidly acting opiate (a drug that is derived from opium). 2  Specifically, heroin is produced from morphine, which is a principal component of opium. 3  Opium is a naturally occurring substance that is extracted from the seedpod of the opium poppy. (Generally, the purer the heroin the whiter the color, because variations in color result from the presence of impurities.) In the western United States, most of the heroin available is a solid substance that is black in color. 2  This type of heroin, known as black tar, may be sticky (like tar) or hard to the touch.