The Menstrual Cycle

Question 1

The Menstrual Cycle

Answer 1

The Menstrual Cycle refers to the changes that occur in the ovary and uterus of a female over a period of about 28 days, for the purpose of fertilization

Question 2

The Ovarian Cycle

Answer 2

the Ovarian Cycle describes what happens inside the ovary as the ovum develops inside the Graafian Follicle, which then releases the ovum to become a corpus luteum

Question 2

The Ovarian Cycle and Ovulation

Answer 2

Under the influence of the follicle stimulating hormone (FSH) produced by the hypophysis/ pituitary gland
The follicle in the ovary becomes a Graafian Follicle containing a mature ovum
The Graafian Follicle produces a hormone Oestrogen which starts the preparation of the uterus for attachment of the fertilized ovum
Approximately every 4 weeks (28 days), the Graafian Follicle ruptures (break open) to release an ovum. This is called ovulation
The ovum is collected by the funnels of the Fallopian Tube
The Luteinizing Hormone (LH), also produced by the pituitary gland helps convert the ruptured follicle into a structure called a corpus luteum
The corpus luteum secretes the hormone progesterone which maintains pregnancy
If fertilization does not take place, the corpus luteum degenerates and progesterone production drops
The unfertilized ovum passes down the fallopian tube, into the uterus and leaves the body

Question 2

The Uterine Cycle

Answer 2

The Uterine Cycle describes the changes that take place in the wall of the uterus as it gradually thickens, becomes enriched with blood vessels up until the endometrium wall tears away accompanied by breeding

Question 3

The Uterine Cycle and Menstruation

Answer 3

The Graafian Follicle produces a hormone Oestrogen which starts the preparation of the uterus for attachment of the fertilized ovum by making the endometrium:
Thicker
More Vascular (Increased blood supply)
More Glandular
This happens because the uterus is preparing itself for attachment of the fertilized ovum, just in case fertilization takes place
After the ovum is released through ovulation, the corpus luteum produces the hormones progesterone, which continues the preparation of the uterus, just in case fertilization takes place
If the ovum is fertilized by a sperm cell, the corpus luteum continues secreting progesterone, which makes certain that the embryo remains attached to the uterine wall i.e. it ensures that pregnancy is maintained
if the ovum is not fertilized, the corpus luteum is destroyed. Progesterone secretion drops and menstruation occurs
During menstruation, the endometrium lining of the uterus comes off as the menstrual period. This is accompanied by bleeding