A NATO official, speaking on condition of anonymity, pointed out that after the attacks NATO sent AWACS planes to patrol American skies and deployed a third of the troops in Afghanistan for more than a decade; more than 1,000 soldiers from non-U.S. NATO allies and partners were killed there, the official pointed out.
Cells in the human body have 46 chromosomes, including 22 pairs of autosomes and one pair of sex chromosomes (XX in females, XY in males). Because there are two sets of chromosomes, one from each parent, the cells are considered diploid.
sex chromosome - (genetics) a chromosome that determines the sex of an individual; mammals normally have two sex chromosomes chromosome - a threadlike strand of DNA in the cell nucleus that carries the genes in a linear order; humans have 22 chromosome pairs plus two sex chromosomes