Which of the following describes the event of ovulation?
The fallopian tube moves the ovum to the uterus.
The oocyte undergoes its first meiotic division.
The Graafian follicle releases an ovum.
The corpus luteum produces progesterone.
The Correct Answer and Explanation is :
Correct Answer:
The Graafian follicle releases an ovum.
Explanation:
Ovulation is the process in which a mature egg (ovum) is released from the Graafian follicle in the ovary and enters the fallopian tube, where it may be fertilized by sperm. This event typically occurs around day 14 of a 28-day menstrual cycle and is triggered by a surge in luteinizing hormone (LH) from the anterior pituitary gland.
During the follicular phase, several follicles in the ovary begin to mature under the influence of follicle-stimulating hormone (FSH). However, only one dominant follicle, known as the Graafian follicle, fully matures and prepares for ovulation. Just before ovulation, the oocyte within the follicle completes the first meiotic division, resulting in a secondary oocyte and a polar body. The secondary oocyte is then released into the fallopian tube.
The fallopian tube does not move the ovum to the uterus immediately after ovulation. Instead, the fimbriae of the fallopian tube sweep the ovulated egg into the tube, where it may encounter sperm for fertilization.
The corpus luteum, which forms from the remains of the Graafian follicle after ovulation, produces progesterone to support the uterine lining for possible implantation. However, this occurs after ovulation, not as part of the ovulation process itself.
Thus, the most accurate description of ovulation is that the Graafian follicle releases an ovum, marking the transition from the follicular phase to the luteal phase of the menstrual cycle.