Structure and function of the genital system
The genital system is different in men and women. In women, it consists of the ovaries, the fallopian tubes, the uterus and the vagina (Fig. 1). In men, it consists of the testicles, the epididymis, the vas deferens, the seminal vesicles, the prostate and the penis (Fig. 2).
These organs are fixed in their anatomically correct position in the lesser pelvis by ligaments and the pelvic floor muscles. The pelvic floor muscles are perforated by the urethra and the rectum as well as by the vagina in women.
The female genital system
The female genital system consists of the ovaries, fallopian tubes, uterus and vagina (Fig. 1).
The ovaries form a pair. In them, the eggs, which are already present at birth, mature. The mature egg cell is contained in a follicle. About every 4 weeks a follicle releases an egg from the ovaries into the fallopian tubes (ovulation). This begins in women between the age of 11 and 15, and ends at the end of menopause. The fertilisation of the mature egg takes usually place in the fallopian tube.
The fallopian tubes flow into the uterus, a hollow muscular organ. Between the 14th and 21st day of the menstrual cycle, a mucous membrane well-supplied with blood begins to form under the influence of hormones, as a prerequisite for the implantation of a fertilised egg. The uterus narrows towards the cervix and ends at the external orifice, which extends into the vagina.
The vagina is a muscular tube and serves as the birth canal. The vaginal opening lies directly behind the urethra orifice and in front of the rectal orifice. The outer female reproductive organs consist of the inner and outer labia and the clitoris.
The male genital system
The male genital system consists of the testicles, epididymis, vas deferens, seminal vesicles, prostate and penis (Fig. 2).
The testicles form a pair. They first develop in the abdominal cavity and only descend into the scrotum shortly before birth. The scrotum protects the testicles and keeps them warm. The testicles are the male gonads in which sperm and the most important male sex hormone, testosterone, are produced. In the epididymis the sperm mature fully and gain their motility.
From the testicles, the sperm enter the urethra via the vas deferens. The vas deferens cross the ureters behind the bladder and lead through the prostate gland. During ejaculation, seminal fluid is added to the sperm by the prostate and seminal vesicles.