Describe the changes that take place during the menstrual cycle from Day 5-13 to the following:
a. Unfertilized egg in ovary
b. Uterus lining

Between days 5 and 13 of a woman's menstrual cycle, an unfertilized egg in ovary prepares its development and maturation within the follicle, while the lining of the uterus -the endometrium- progressively enlarges.

Explanation:

Under normal conditions, a woman's menstrual cycle lasts 28 to 30 days, during which time both hormonal and physiological changes occur as part of the reproductive process.

Menstruation occurs as a result of the shedding of the endometrium, which had previously developed to facilitate the implantation of a possible pregnancy. This phase usually lasts five days and is characterized by genital bleeding.

From the fifth to the 13th day, a woman's reproductive system undergoes changes in preparation for possible fertilization and pregnancy:

The unfertilized egg is found inside the ovarian follicle, maturing before its imminent release, under the influence of follicle-stimulating hormone (FSH). The maturation of a few follicles occurs simultaneously, but only one will reach the necessary maturity to allow the release of the egg. The lining of the uterus, called the endometrium, receives signals from the hormone estradiol -produced by the mature ovarian follicle- and induces proliferation and thickening of the endometrium.

Approximately on the 15th day of the menstrual cycle, the egg is released and it is the time when it can be fertilized by a sperm to produce the zygote, which will start a pregnancy in women.

Learn more:

Purpose of the menstrual cycle link

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