During bleeding phase of menstrual cycle unfertilised secondary oocyte...
If fertilisation does not occur, the secondary oocyte undergoes autolysis and progesterone (secreted by persistent corpus luteum) inhibits the release of LH from pituitary. Reduction of LH level causes regression of corpus luteum by autolysis and thus fall in the progesterone level in the blood. Due to deficiency of progesterone, uterine lining sloughs off causing bleeding. This whole phase is called bleeding phase.
This question is part of UPSC exam. View all NEET courses
During bleeding phase of menstrual cycle unfertilised secondary oocyte...
Explanation:
During the menstrual cycle, the interplay of hormones is crucial in regulating the various phases of the cycle. Let's break down the options given and explain why option C is the correct answer:
a) Progesterone and estrogen continue the hypertrophy of endometrial lining:
- This statement is incorrect because during the bleeding phase of the menstrual cycle, the endometrial lining is shedding and being eliminated. Progesterone and estrogen are involved in building up the endometrial lining during the previous phase (proliferative phase) of the menstrual cycle, but not during the bleeding phase.
b) Prolactin and progesterone reduce LH level causing regression of corpus luteum:
- This statement is partially correct. Prolactin and progesterone do play a role in reducing the levels of luteinizing hormone (LH), which ultimately leads to the regression of the corpus luteum. However, this occurs during the luteal phase of the menstrual cycle, not during the bleeding phase.
c) Progesterone inhibits the release of LH from the pituitary causing regression of corpus luteum:
- This statement is correct. During the bleeding phase of the menstrual cycle, the corpus luteum from the previous cycle starts to regress. Progesterone, which is produced by the corpus luteum, inhibits the release of luteinizing hormone (LH) from the pituitary gland. This decrease in LH levels leads to the regression of the corpus luteum.
d) Prolactin and estrogen inhibit progesterone secretion leading to sloughing off uterine lining:
- This statement is incorrect. Prolactin and estrogen do not directly inhibit progesterone secretion during the menstrual cycle. Progesterone levels decrease naturally when the corpus luteum regresses, leading to the sloughing off of the uterine lining during the bleeding phase.
In conclusion, option C is the correct answer as it accurately describes the hormonal interplay during the bleeding phase of the menstrual cycle. Progesterone inhibits the release of LH from the pituitary, causing regression of the corpus luteum.
To make sure you are not studying endlessly, EduRev has designed NEET study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in NEET.