Females have two copies of the X chromosome, while males have one X and one Y chromosome. The 22 autosomes are numbered by size. The other two chromosomes, X and Y, are the sex chromosomes. This picture of the human chromosomes lined up in pairs is called a karyotype.
Of the 23 pairs of chromosomes, the first 22 pairs are called "autosomes." The final pair is called the "sex chromosomes." Sex chromosomes determine an individual's sex: females have two X chromosomes (XX), and males have an X and a Y chromosome (XY).
During mitosis the four centrioles appear visibly and move to the ends of the nucleus one pair at each end<span> then they produce a series of threads that attach to the chromosomes During cell division the threads split the chromosomes and drew them towards the centrioles</span>
The most Senistive part of the chest
