Menstrual cycle
Read the following passage carefully and answer the given questions.
The reproductive cycle in the female primates is called menstrual cycle. The first menstruation begins at puberty and is called menarche. The cyclical changes in the ovary and the uterus during menstrual cycle are induced by changes in the levels of pituitary and ovarian hormones. One ovum is released during the middle of each menstrual cycle. The cycle starts with the menstrual phase, when menstrual flow occurs and it lasts for 3-5 days. Menstruation only occurs if the released ovum is not fertilised. Lack of menstruation may be indicative of pregnancy. 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. The secretion of gonadotropins increases gradually during the follicular phase, and stimulates follicular development as well as secretion of estrogens by the growing follicles. Both LH and FSH attain a peak level in the middle of cycle. Rapid secretion of LH leading to its maximum level during the mid-cycle called LH surge which induces rupture of Graafian follicle and thereby the release of ovum. The ovulation is followed by the luteal phase.
Identify the proliferative phase.
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Follicular Phase
The passage says that during the follicular phase, the primary follicles in the ovary grow into a fully mature Graafian follicle, and at the same time the endometrium of the uterus regenerates through proliferation. Because the uterine lining grows again in this phase, the follicular phase is also called the proliferative phase.
(1) Menstrual Phase — Incorrect. In the menstrual phase the endometrium breaks down; it does not grow.
(2) Luteal Phase — Incorrect. The luteal phase is also called the secretory phase, because the corpus luteum secretes large amounts of progesterone in it.
(3) Follicular Phase — Correct. The endometrium proliferates during the follicular phase.
(4) Ovulation — Incorrect. Ovulation is the release of the ovum from the Graafian follicle in the middle of the cycle, caused by the LH surge. It is not the proliferative phase.
Note: The passage is taken from NCERT. NTA has put lines of the NCERT text together to make it. Most CUET (UG) questions come straight from NCERT, so study the book line by line, including figures and their titles.