Egg Cell Maria Paula Coz, Daniela Mazzetti & Gabriela Echeandía 9ºA

Location All of the immature egg cells a woman will ever produce are stored in the ovaries by the time she is born. During each menstrual cycle, hormonal messages from the brain cause the ovaries to develop a single mature egg cell for fertilization.

Ovaries They are a pair of female reproductive organs, located in the pelvis (one on each side of the uterus). The ovaries are connected to each other by the Fallopian tubes. They are the main source of female hormones (estrogen and progesterone)and they also regulate the menstrual cycle and pregnancy.

Ovulation During Ovulation and immediately after, the uterus lining thickens in preparation for a fertilized egg. Ovulation occurs each month when the ovaries are stimulated by the hormones FSH (Follicle Stimulating Hormone) and LH (Leutinizeing Hormone). Once the egg matures it is ovulated, and it travels through the fallopian tubes to the uterus.

Fertilization Fertilization occurs in oviducts (fallopian tubes) of the female reproductive tract. Only one of the approximately 300 million sperm that released into a female's vagina can fertilize the single female egg cell. The successful sperm cell must enter the uterus and swim up the fallopian tube to meet the egg cell, where it passes through the thick coating surrounding the egg. This coating, consisting of sugars and proteins, is known as the “Zona Pellucida ”. The ovum is fertilized inside the female body, and the embryo then develops inside the uterus, receiving nutrition directly from the mother.