Female Reproductive System & Menstrual Cycle

Question 1

What is the function of the female reproductive system?

Answer 1

Producing a small number of ova (mature egg cells).
Provides a suitable site for the fertilisation of an ovum by a sperm.
Provides an environment in which the embryo can be nourished, develop and mature.

Question 2

What makes up the external genitalia of the female reproductive system?

Answer 2

Collectively known as the vulva.
Mons pubis
Perineum
Labia majora/labia minora
Clitoris
Vaginal orifice

Question 3

What is the mons pubis?

Answer 3

fatty tissue that lies above the symphysis pubis of the pelvis and is covered by skin and hair.

Question 4

What is the perineum?

Answer 4

strong muscles which support the internal organs of the pelvic cavity.

Question 5

What are the labia majora and minora and its main function?

Answer 5

Labia majora: two folds of fatty tissue covered with skin. The inner surface is smooth and contains sweat and sebaceous glands. Main function is to protect the vagina.
Labia minora: two folds of skin lying within the labia majora and contains a few sweat sebaceous glands and also protects the vagina.

Question 6

What is the clitoris and function?

Answer 6

a small projection of erectile tissue which is richly supplied with blood vessels and nerve fibres. It promotes pleasure of sexual intercourse

Question 7

What is vaginal orifice?

Answer 7

situated between the two pairs of labia in an area commonly known as the vestibule and is covered internally by a membrane of skin called hymen. At the entrance of the vaginal orifice lie the ducts of a pair of glands which secrete mucus to moisten the external genitalia. It allow access to the internal genitalia.

Question 8

What makes up the internal genitalia of the female reproductive system?

Answer 8

The vagina
The uterus
The fallopian tubes
The ovaries

Question 9

What is the vagina and its function?

Answer 9

an elastic, fibromuscular canal that extends from the vulva to the uterus. Where the cervix projects into the vagina, four recesses are formed.

The function of the vagina are:
Allows the deposit and passage of spermatozoa during sexual intercourse.
Provides an outlet for the fetus and other products of conception.
Provides an outlet for the menstrual flow and also acts as a barrier to ascending infections.

Question 10

What are the four layers of the vagina?

Answer 10

The vaginal walls are composed of four layers:
Inner layer of squamous epithelium forming folds which allow the vagina to expand enormously to allow the passage of a fetus.
Layer of connective tissue containing blood vessels
Muscle layer consisting of an outer layer of longitudinal muscle and an inner layer of circular muscles
Outer layer of connective tissue with other organs of the pelvis and contains blood and lymphatic vessels and nerve fibres.

Question 11

What is the uterus and its function?

Answer 11

is a muscular organ situated in the pelvic cavity between the bladder and the rectum. It’s length is around 7.5 cm long weighing 50-70 g and in pregnancy it is around 30 cm long weighing 800-1200 g.

The functions are:
To prepare to receive, protect and nourish a fetus.
To assist in the expulsion of the fetus, placenta and membranes at delivery.
To control blood loss from the placental site.

Question 12

What are the three layers of the uterus?

Answer 12

Endometrium, inner epithelium: made up of two layers, the functional (sheds during each menstrual cycle and also provides nourishment for the fertilised ovum which becomes embedded in this layer) and basal layer (gives rise to the functional layer after each menstruation).
Myometrium, muscle layer (circular, oblique and longitudinal) thickest at the fundus of the uterus and this layer plays a role in during the process of pregnancy and childbirth.
Perimetrium, connective tissue and is draped over the uterus and uterine tubes.

Question 13

What is the fallopian tube and its function?

Answer 13

extends laterally from each side of the uterus and have the main functions of propelling the ovum towards the uterus and provides a passage for the spermatozoa to meet the ovum for fertilisation

Question 14

What are the ovaries and its function?

Answer 14

the female gonads and lie on either side of the uterus and have a function of producing ova during the fertile years and also produces oestrogen and progesterone. The ovaries are covered by the peritoneum and is enclosed in a tough fibrous membrane. The medulla contains blood and lymphatic vessels and the cortex contains ovarian follicles that undergo several stages of development during the 28 days of an average reproductive cycle.

Question 15

What is the outcome of the reproductive system?

Answer 15

The release of an ovum from the ovary

The preparation of the uterus to receive a fertilised ovum

Question 16

What happens during the ovarian cycle?

Answer 16

The hypothalamus produces gonadotrophin-releasing hormone (GnRH) in response to low levels of oestrogen and progesterone.
The high level of GnRH stimulates the secretion of follicle-stimulating hormone (FSH) and controls the growth and maturation of the secondary follicle which begins to secrete oestrogen.
several primordial follicles start to mature under the influence of follicle-stimulating hormone.
Once one follicle matures → graafian follicle, it migrates to the surface of the ovary.
So much pressure is created internally due to the increased fluid it secretes and makes the covering of the follicle thin till it ruptures thus releasing the ovum into the fallopian tube → OVULATION.
The follicle becomes a corpus luteum and functions as an endocrine gland producing oestrogen and progesterone for 14 days and then degenerates if fertilisation does not take place. High oestrogen levels inhibits the release of FSH and instead the AP gland releases luteinising hormone (LH). → A SUDDEN INCREASE OF LH INITIATES OVULATION.

Question 17

What happens during the menstrual cycle?

Answer 17

The different levels of oestrogen and progesterone affects the endometrium of the uterus (basal and functional layer).
The development of the endometrium goes through three phases:
0-4 DAYS: MENSTRUAL PHASE
Endometrium sheds down to basal layer.
Due to the spiral arteries of the endometrium go into spasm.
Resulting in the cells of the endometrium to die.
Muscular contractions expel the dead tissue through the cervix.
4-14 DAYS: PROLIFERATIVE PHASE
Endometrium thickens under the influence of oestrogen from Graafian follicle
Ovulation may occur at day 14
This is the phase that can vary in time if cycles are longer or shorter.
14-26 DAYS: SECRETORY PHASE
Endometrium becomes more vascular under the influence of oestrogen and progesterone from the corpus luteum.
The lining becomes more vascular.
These conditions are optimal 7 days after ovulation and the time when a fertilised ovum is most likely to enter the uterus for embedding.