After fertilization, the embryo moves to which structure where the uterine lining thickens in response to hormones?

• A. Fallopian tube
• B. Cervix
• C. Uterus
• D. Ovary

Answer: (C)

The uterus is the site where the lining becomes thick and ready to accept an embryo. After fertilization, the developing embryo travels down the fallopian tube and reaches the uterus, where the endometrium has thickened under hormonal influence. Estrogen drives growth and vascularization of this lining, while progesterone switches it to a secretory state that supports implantation and early pregnancy. Once implanted, the embryo relies on this prepared environment for nourishment and stability.

The other structures aren’t where this hormonal thickening occurs: the fallopian tube is the usual site of fertilization and transportation toward the uterus; the cervix is the lower part of the uterus not involved in presenting a receptive lining for implantation; and the ovary produces eggs and hormones but does not provide the thickened endometrium needed for implantation.