Reproductive system

The external organs of the female reproductive system are contained in an area called the vulva. This includes the entrance to the vagina which leads to the uterus. It provides a double layer of protection through the outer (labia majora) and inner labia (labia minor).

The internal organs of the female reproductive system:

Vagina

The vagina extends from the vulva to where it opens to form the vaginal opening.

Functions

• Provides a passageway for the foetus to be expelled from the uterus.
• Receives the penis during coitus.
• Allows discharge of menstrual flow.

Uterus

The uterus is a hollow pear-shaped muscular organ and it consists of a fundus, body and cervix. The three layers of the uterine lining are the:

• Perimetrium
• Myometrium
• Endometrium.

Functions

• Receives fertilised ovum (embeds in endometrium) or sheds superficial layer if fertilisation does not take place — menstruation.

• Supports the growth of the foetus during pregnancy.
• Contractions of the uterus propels the foetus to give birth at the end of pregnancy.

Fallopian tubes

These tubes arise from the uterus and fan out to a trumpet-like shape called the fimbriae.

Functions

To transport the ovum from the ovary to the uterus by means of peristalsis with the aid of ciliated cells in the lining. Fertilisation takes place in the distal third of the fallopian tube.

Ovaries

The ovaries are two almond shaped organs - one on either side of the uterus.

Functions

To produce ova (ovulation). Hormone production (begins at puberty). The two female hormones are oestrogen and progesterone.

The menstrual cycle

The monthly cycle of changes in the ovaries and the lining of the uterus (endometrium), starting with the preparation of an egg for fertilization. When the follicle of the prepared egg in the ovary breaks, it is released for fertilization and ovulation occurs.

The main features of the external organs of the male reproductive system are:

Penis

This organ has three parts: the root, which attaches to the wall of the abdomen; the body, or shaft; and the glans, which is the cone-shaped part at the end of the penis. The glans, also called the head of the penis, is covered with a sheath of protective skin called foreskin.

Functions

Penis is the male organ used in sexual intercourse. It conveys urine and seminal fluid to outside the body.

Testes

The testes or testicles are oval-shaped organs that lie in the scrotum and are equivalent to the female ovaries.

Functions

Produce spermatozoa. Produce and secrete male sex hormones (testosterone).

Scrotum

This is the loose pouch-like sac of skin that hangs behind and below the penis. It contains the testes, as well as many nerves and blood vessels.

Functions

Encloses and protects the testes.

The main features of the internal organs of the male reproductive system are:

Epididymis

The epididymis is a long, coiled tube that rests on the backside of each testicle.

Functions

The job of the epididymis to bring the sperm to maturity (since the sperm that emerge from the testes are immature and incapable of fertilization). It then transports the sperm cells to the vas deferens.

Vas deferens

The vas deferens is a long, muscular tube that travels from the epididymis into the pelvic cavity, to just behind the bladder.

Functions

Store spermatozoa. Convey spermatozoa to ejaculatory ducts.

Ejaculatory ducts

These are formed by the fusion of the vas deferens and the seminal vesicles. The ejaculatory ducts empty into the urethra.

Functions

Receive sperm and additives to produce seminal fluid.

Urethra

The urethra is the tube that carries urine and semen from the bladder to outside of the body

Functions

Serves the dual purpose of conveying urine from the body and semen.

Seminal vesicles

The seminal vesicles are sac-like pouches that attach to the vas deferens near the base of the bladder. The fluid of the seminal vesicles makes up most of the volume of the ejaculatory fluid.

Functions

The seminal vesicles produce a sugar-rich fluid that provides sperm with a source of energy to help them move.

Prostate gland

The prostate gland is a small ball-shaped structure that is located below the urinary bladder in front of the rectum.

Functions

Secretes an alkaline fluid that helps neutralise acidic seminal fluid and enhances motility of sperm.