Arrange the following structures involved in menstrual cycle in correct sequence.
A. Corpus luteum
B. Graafian follicle
C. Ovum
D. Primary follicle
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → D, B, C, A
D. Primary follicle — this comes first. At the start of the cycle the primary follicles in the ovary begin to grow.
B. Graafian follicle — this comes second. A follicle grows to become the fully mature Graafian follicle by the middle of the cycle.
C. Ovum — this comes third. The Graafian follicle ruptures and releases the ovum. This is ovulation.
A. Corpus luteum — this comes last. The remains of the ruptured follicle change into the corpus luteum, which secretes progesterone.
NCERT Extract:
Menstrual Cycle – “… The menstrual phase is followed by the follicular phase. During this phase, the primary follicles in the ovary grow to become a fully mature Graafian follicle and simultaneously the endometrium of uterus regenerates through proliferation.”
Menstrual Cycle – “… Rapid secretion of LH leading to its maximum level during the mid-cycle called LH surge induces rupture of Graafian follicle and thereby the release of ovum (ovulation). The ovulation (ovulatory phase) is followed by the luteal phase during which the remaining parts of the Graafian follicle transform as the corpus luteum (Figure 2.9).”