Zygote - From “Blackberry” To Embryo

After fertilization, when the sperm's genetic material complements the nuclear contents of the egg to form a cell with 46 chromosomes, the resulting cell - the zygote - is sent to the uterus, where it resides and develops for nine months.

As it moves toward the uterus, the zygote splits and forms a dense conglomerate of 16 or 32 new cells - a morula, similar to a blackberry.

2 blastomeres
4 blastomeres
8 blastomeres
32 blastomeres
morula
blastomeres

Blastomers, morula cells, secrete a serous fluid that fills the inside of the conglomerate and form a cavity in it. In this state, the blastula, a primitive organism similar to a hollow ball, attaches to the walls of the uterus. Implantation (introduction into the wall of the uterus) occurs on the sixth or seventh day after fertilization.

In the uterus, cells continue to fragment and begin to specialize in order to then create all the tissues and organs of the embryo, the future human body. In the third week, structures appear that form various organs, the skeleton, blood vessels and the nervous system.