Which phase follows fertilization in the process of mammalian reproduction?

• A. Implantation
• B. Mitosis
• C. Meiosis
• D. Ovulation

Answer: (B)

In mammalian reproduction, fertilization is the process where a sperm cell fuses with an egg cell to form a zygote. The phase that follows fertilization logically includes the series of developmental steps the zygote undergoes as it begins to divide and grow.

After fertilization, the zygote undergoes multiple rounds of cell division, beginning with the first mitotic division. Mitosis is the process by which a single cell divides to produce two genetically identical daughter cells, and it is through this method that the zygote develops into a multicellular embryo. Hence, the correct answer reflects this fundamental biological process that is essential for subsequent development.

Implantation, while an important phase in development, happens after the zygote has already gone through several rounds of mitosis and has developed into a blastocyst that is ready to attach to the uterine wall. Meiosis occurs prior to fertilization, generating the gametes (sperm and egg), and ovulation is the release of the egg from the ovary, which also precedes fertilization. Thus, the correct answer emphasizes the critical role of mitosis in the immediate continuation of development following fertilization.