There are almost as many different types of four-wheel-drive systems as there are four-wheel-drive vehicles. It seems that every manufacturer has several different schemes for providing power to all of the wheels.
Human Male Chromosomes. In the normal karyotype of male chromosomes, 23 pairs of very long DNA molecules and their associated proteins carry the hereditary information of a man.
Males have two distinct sex chromosomes (XY), and are called the heterogametic sex. Humans, as well as some other organisms, can have a chromosomal arrangement that is contrary to their phenotypic sex, that is, XY males or XX females. Source(s): timmyyy. renerade Â· 8 years ago.