(a(i))[2]
Use Fig. 4.1 to state the time at which each of the following happens: the uterus lining reaches maximum thickness; the concentration of progesterone starts to rise.
(a(ii))[1]
Draw a ring around the day in Fig. 4.1 when ovulation is most likely to occur.
(a(iii))[2]
Explain how it can be concluded from Fig. 4.1 that the person did not become pregnant during the 28 days shown, even though ovulation occurred.
(b)[4]
The menstrual cycle is regulated by hormones. Name two hormones, other than progesterone, that regulate the menstrual cycle. State one role of each hormone.