Describe the process of implantation of the embryo.

(N/A) As the zygote moves through the isthmus of the oviduct towards the uterus,it undergoes mitotic divisions called cleavage,forming $2, 4, 8,$ and $16$ daughter cells known as blastomeres.
The embryo containing $8$ to $16$ blastomeres is called a morula.
The morula continues to divide and moves further into the uterus,where it transforms into a blastocyst.
The blastomeres in the blastocyst are arranged into an outer layer called the trophoblast and an inner group of cells attached to the trophoblast called the inner cell mass.
The trophoblast layer then gets attached to the endometrium,and the inner cell mass gets differentiated as the embryo.
After attachment,the uterine cells divide rapidly and cover the blastocyst.
As a result,the blastocyst becomes embedded in the endometrium of the uterus. This process is called implantation and it leads to pregnancy.