Basic  Human Genetics 1

You typically have 46 chromosomes in the nuclei of your cells.

         22 Pairs of Autosomes - the non sex chromosomes
           
          2  Sex chromosomes - so called because they determine your gender.


If you have 2 "X" chromosomes, you're a woman.

If you have an "X" and a "Y" chromosome, you're a man.


       These 46 chromosomes are in the nucleus of a cell.  The nucleus is the control center of the cell, and the chromosomes are like the computers that make code to run what the functions of that cell is.


Outside the nucleus, there are other parts, and one of those are the mitochondria.  They also contain their own DNA.

      The DNA in the Mitochondria is called mitochondrial DNA, or mtDNA.  It codes for the making of new mitochondria.

DNA is a very large molecule that makes up most of each chromosome.  When the cells gets ready to divide, the chromosomes coil up into the X shape that you typically see a chromosome depicted as.  Usually though, they are uncoiled so they can be accessed by the cell's machinery to make the code for all the enzymes and other proteins the cell needs.