Q21 - Hormonal Control of the Menstrual Cycle
The menstrual cycle is the regular natural change that occurs in the female reproductive system. In the ovary, where oogenesis take place, each cycle can be divided into three phases consisting of the follicular phase, ovulation and luteal phase. The menstrual cycle is controlled by hormones of hypothalamus-pituitary-ovary axis. The figure shows alternations in body temperature and hormonal changes during the menstrual cycle.
Figure 1.
Using the information and data, determine which of the statements are true or which are false.
A. The increase shown at point A is caused by the effect of oestrogen on the anterior pituitary.
B. Curve B shows changes in progesterone level during menstrual cycle.
C. The source of the increase in concentrations indicated at point C and D are granulosa cells and corpus luteum, respectively.
D. Substance E is secreted by follicular cells.
E. The cause of the sudden increase shown at point E is positive feedback of oestrogen on the anterior pituitary and absence of progesterone.
Question reproduced from IBO 2018, Theoretical Paper 2, licensed under CC BY-NC-SA 4.0 - attributed to the International Biology Olympiad. Open the full exam PDF · Community solutions (unofficial)