Answer:
meiosis
Explanation:
Mitosis creates two identical daughter cells that each contain the same number of chromosomes as their parent cell. In contrast, meiosis gives rise to four unique daughter cells, each of which has half the number of chromosomes as the parent cell.
When a lineage splits into multiple line of descents, then, it leads to speciation. It is a process by which a single population evolves into different species. The process of speciation leads to the development of two or more species as the lineages are splitted. These two evolved species are genetically independent.
Hence, the blank can be filled with 'speciation'.
Because the majority of cell differentiation occurs during the EMBRYONIC phase, .................. The embryonic stage of pregnancy is the period after implantation during which all the important organs and structures in the growing fetus is formed. Tetratogens are factors that caused malformation of embryo. Exposure to tetratogens during embryonic stage cause most destructive damages.