Your little zygote has now officially turned into an embryo ... they’ll combine to create the full 46 chromosomes (two sets of 23, one from each gamete) needed for a full human cell.

Each human has 46 chromosomes, 22 pairs of autosomes ... During oogenesis and spermatogenesis, each parent contributes 23 chromosomes to the zygote through a process of chromosomal reduction ...

The zygote inherits two fully active X chromosomes and begins re-inactivation of the paternal X chromosome (XP) at the 4- to 8-cell stage. In the trophectoderm (extra-embryonic cells, shown in ...