i) The menstruation cycle is the time period during which the unfertilized egg and the uterine wall linings are discharged through the vagina when the fertilization of the egg by the sperm does not take place in the female body.

ii) The changes that take place in a woman are as follows:

iii) The ovaries release an egg every month and hence the walls of the uterus already prepare itself for embedding and nourishing the embryo. This causes the uterine walls to thicken and become spongy.

iv) When the egg does not get fertilized, it remains viable for a day after which it does not survive.

v) Since the egg does not get embedded in the walls of the uterus, the thick lining is not needed anymore and it sheds off in the form of blood and mucous which comes out of the vagina.

vi) The process takes place every month and is known as the menstrual cycle which lasts for about 2-8 days every month.

vii) Females experience some changes in their body during the menstrual cycle. Apart from the bleeding from the vagina during this period, there is fluctuation in the level of certain hormones in the body which sometimes lead to mood swings. Abdomen cramps are also common during the menstrual cycle.