When does the embryo stop dividing and start developing body parts?
The embryo's rapid cell division and multiplication continues until about 16 to 32 cells. Then, at approximately 32 cells, and sometimes at 64, that division stops. At that point, the body cells begin developing, forming extremities such as fingers, feet, and legs.
Les explains that after the young mother becomes pregnant and the ovum is impregnated, the first thing that happens is the cells begin to divide and multiply rapidly. They become two, four, eight, and so on, up until about 16 to 32 cells. Then, at about 32 and sometimes at 64, the process of cell division and multiplication stops, and the body cells begin to develop. Les clarifies that by "body cells" he means the extremities—the fingers, feet, and legs—all of which will form the little human body.