List and briefly describe the three periods of prenatal development, noting the event that marks the beginning of each period

Question

What will be an ideal response?

Answer 1

The germinal period begins with conception, which typically occurs in the fallopian tube. The conceived zygote begins to divide, forming a blastocyst, which continues to divide and grow as it moves down the fallopian tube to the uterus. The embryonic period begins with implantation of the blastocyst in the uterus. Cell differentiation continues at a rapid pace, and toward the end of the embryonic period, the embryo appears distinctly human in form. The indifferent gonad also develops toward the end of this period. The fetal period begins at the two-month point and continues until birth. Differentiation of body structures continues throughout, and the developing child typically reaches the age of viability at 22 to 28 weeks after conception.