In which of the following structures does fertilization of an ovum by a spermatozoa occur?
A.
Ovary
B.
Uterus
C.
Fallopian tube
D.
Cervix
The Correct answer and Explanation is:
The correct answer is C. Fallopian tube.
Explanation:
Fertilization, the process where a spermatozoon (sperm) merges with an ovum (egg), typically occurs in the fallopian tubes, also known as uterine tubes or oviducts. These tubes play a critical role in reproduction, serving as the pathway for the egg to travel from the ovary to the uterus.
During ovulation, which is part of the menstrual cycle, an ovary releases an egg into the pelvic cavity. The fimbriae, which are finger-like projections at the end of each fallopian tube, help guide the egg into the tube. Once the egg is within the fallopian tube, it is available for fertilization. Sperm, introduced into the female reproductive tract during intercourse, swim through the cervix and uterus, ultimately reaching the fallopian tubes.
Fertilization typically happens in the ampulla, the widest section of the fallopian tube. Here, the sperm penetrates the egg’s outer layer, leading to a series of chemical changes that prevent additional sperm from entering the egg, ensuring that only one sperm fertilizes the egg. This single fertilization event leads to the formation of a zygote, which begins to divide and develop as it travels back down the fallopian tube toward the uterus for implantation.
In contrast, the ovary is responsible for producing and releasing eggs, the uterus serves as the site for implantation and fetal development, and the cervix acts as a barrier between the uterus and the vagina. It also allows passage for sperm and menstrual fluid but is not involved in fertilization itself. Thus, the fallopian tube is the critical structure for the fertilization process, making it essential for successful conception.