Answer:
Meanwhile, the ovary itself releases a hormone called estrogen which causes the uterine lining to increase in thickness. The uterine lining becomes thicker so that the fertilized egg can attach to it. It is correct.
Explanation:
The hypothalamus, which is in the brain, releases a hormone called Gonadotrophin Release Hormone (GnRH). GnRH travels to the hypophysis, which is a gland located in the lower part of the skull. The GnRH makes the hypophysis release a hormone called Follicle Stimulant Hormone (FSH). This hormone travels to the ovaries, making it release estrogen. This hormone is in high concentrations during the 4th or 6th day of the cycle up to the 14th day, which is when ovulation happens. Estrogens make the endometrium, which is the outer layer of the uterus, grow making it thicker to prepare itself to attach the fertilized egg and provide to it the necessary nutrients to grow.
If the fertilization does not happen, the thickened endometrium will be expelled from the uterus some days later during menstruation.
