What is a morula?

A morula is a stage of embryonic development that occurs after the zygote undergoes several rounds of cell division. It is a solid mass of cells that are identical and closely packed together, resembling a mulberry, which is where the term "morula" comes from.

The morula stage typically consists of around 16-32 cells and is formed around 3-4 days after fertilization. These cells are totipotent, meaning they have the potential to develop into any cell type in the body.

After the morula stage, the embryo undergoes further cell divisions and begins to form a fluid-filled cavity, transitioning into the blastula stage. The blastula will go on to develop into the more complex structures of the embryo, eventually leading to the formation of a fetus.

The morula stage is a critical point in embryonic development, as it marks the beginning of the differentiation process where cells start to specialize and take on specific roles in the body.