*Protect and nourish the fertilized egg until it is fully develop
Sexual reproduction would not be possiblewithout the sexual organs called gonads. Both sexes have gonads, in men are the testes and in female are the ovaries. The female gonads produce female gametes (eggs); the male gonads produce malegametes (sperm). Once an egg is fertilized by the sperm, it is called zygote.
When a woman is born, her ovaries contain hundreds of thousands of eggs, which remain inactive until puberty begins. Atpuberty, the pituitary gland, located in the central part of the brain, starts making hormones that stimulate the ovaries to produce female sex hormones, including estrogen. The secretion of thesehormones causes a girl to develop and transform into a mature woman.
Towards the end of puberty, girls begin to release eggs as part of a monthly period called menstrual cycle. About once a month, duringovulation, an ovary sends a tiny egg into the fallopian tube. Unless the egg is fertilized by a sperm while in the fallopian tube, it dried and leaves the body about two weeks later through the uterus.This process is called menstruation. The blood and tissues of the lining of the uterus combine to form the menstrual flow, which in most girls lasts from 3 to 5 days. The first period of a girl iscalled menarche.
Normally, women and girls feel some discomfort in the days before their periods. Premenstrual syndrome (PMS) includes physical and emotional symptoms. These symptoms include acne,bloating, breast pain, constipation, diarrhea, food cravings, depression, irritability, difficulty concentrating, and stress management. PMS is usually worse during the 7 days prior to the beginning ofthe period and disappears once it begins. Many women also experience abdominal cramps during the first days of the period. These are caused by prostaglandins, chemicals in the body, which make the...