What term describes the early developmental process where cell divisions lead to multicellular formation?

The term that describes the early developmental process where cell divisions lead to multicellular formation is cleavage. Cleavage refers to a series of rapid mitotic divisions of the zygote, occurring immediately after fertilization. This process transforms the single-celled zygote into a multicellular structure, known as a morula, and eventually forms a blastula as the cells continue to divide and rearrange. During cleavage, the size of the embryo does not increase significantly, as the divisions occur without substantial growth in cell size. This stage is crucial for setting the stage for later developmental processes such as gastrulation, where the basic body plan begins to establish.