Science Biology - Mitosis Homework Help?

Hi, I have some biology h/wk on mitosis. I understand how the mitosis cycle works (The dna being copied to create 2 nuclei etc.). What I don't understand is at which point is it a mother cell. Is this before anything has happened to the cell (ie. still has only 46 chromosomes (uming in human)) or is it after the chromosomes have been copied (ie. has 92 chromosomes)? I would really appreciate it if someone could let me know at which of these points in the cycle is it the mother cell. Thanks.