Which step comes last in the order of cell development?

The development of a human organism progresses through several key stages, and recognizing the sequence is vital for understanding prenatal development. The final stage in this progression is the fetus.

After fertilization occurs, the first step is the formation of the zygote, which is a single-cell organism formed by the union of sperm and egg. Following this, cleavage begins, leading to the formation of the blastocyst, which is essential for implantation into the uterine wall. Once the blastocyst implants, it develops into an embryo, marking the next phase of development where the basic structures and systems begin to form.

Eventually, after a significant period of development, the embryo progresses to the fetal stage. This stage is characterized by further growth and maturation of the structures that were established during the embryonic phase. The fetus continues developing until birth, gaining weight and refining bodily systems, preparing for life outside the womb. Thus, understanding the fetal stage as the last step emphasizes the culmination of all preceding developmental processes.