Final answer:
After mitosis, the developing egg becomes a solid ball of cells named the morula, which then develops into a blastocyst as it reaches the uterus.
Step-by-step explanation:
By the time the developing egg reaches the uterus after continuous division through mitosis, it has become a solid ball of cells known as the morula.
The morula stage follows the initial cleavage of the fertilized egg and precedes the formation of the blastocyst, which is a more advanced developmental stage with a fluid-filled cavity called the blastocoel and an inner cell mass that will eventually give rise to the embryo.
The processes of mitotic division (cleavage) and the formation of the different cellular structures during these developmental stages are critical for the early stages of embryonic growth.