A: On 12 September 2001, less than 24 hours after the terrorist attacks against the United States, NATO declared the attacks to be an attack against all NATO member countries within the terms of Article 5 of the North Atlantic Treaty.
Humans have an additional pair of sex chromosomes for a total of 46 chromosomes. The sex chromosomes are referred to as X and Y, and their combination determines a personâs sex. Human females have two XX chromosomes while males possess an XY pairing.
Body cells have pairs of chromosomes while sex cells have only single sets of chromosomes. The human body cells have 22 pairs of autosomes and 1 pair of sex chromosomes for a total of 23 pairs or 46 chromosomes. But sex cells (sperm or ovum, known as gametes or diploid cells) contain only 23 chromosomes (unpaired), when they meet (forming a Zygote), the 23 from each male and female gamete form a cell containing 46 chromosomes to make a Haploid cell. Normal body cells (known as a haploid cells) contain 46 chromosomes (or 23 pairs of chromosomes).