Testicles Testicles (diagram 113-115) - are a paired mixed male sex glands, producing male sex cells - sperm, or spermatozoid (exocrine functi

Testicle and epididymis


Testicles (diagram 113-115) — are a paired mixed male sex glands, producing male sex cells — sperm, or spermatozoid (exocrine function), and the male sex hormone testosterone (endocrine function). The testicles are located in the skin and muscle sac — the scrotum (figures 113,114). In the fetus they are formed in the abdomen and immediately after birth or within 1-2 weeks descend into the scrotum. If this did not happen, the parents of the child should see a doctor.

Testicle — is the formation of an oval-shaped volume of 15-25 cm3 and a weight of 20-30 g. Externally it is covered with seven coats. This complex biological membranes is of great importance because the testis maintains a constant temperature that is necessary for the formation of sperm that can fully develop only at a temperature of 2-3 °C below the temperature of the internal organs. Therefore, it is not desirable wearing too tight underwear to men, often taking a hot bath. Each testicle contains approximately a thousand tortuous seminiferous tubules with a total length of 300-400 m. Upon the sexual ripening in the seminiferous tubules of the testicles forms the sperm. From the testicles, it comes to the epididymis, where they are ripening for 80 days (diagram 113). Taken from http://worldofschool.org

Diagram 113. The structure of the male reproductive organs: 1 — the penis; 2 — the urethra; 3 — cavernosum; 4 — the spongy body; 5 — a bunch; 6 — testicle; 7 — convoluted seminiferous tubules testicular; 8 — the head of the penis; 9 — epididymis; 10 — scrotum; 11 — the ureter; 12 — the vas deferens; 13 — the seminal vesicle; 14 — rectum; 15 — bladder; 16 — the coccyx; 17 — ejaculatory ducts; 18 — the prostate gland; 19 — pubic symphysis
Diagram 114. Male sexual gland: 1 — vein; 2 — artery; 3 — the vas deferens; 4 — epididymis; 5 — fascia; 6 — a testicle; 7 — fleshy shell; 8 — tunica vaginalis; 9 — the skin of the scrotum
Diagram 115. The structure of the testicles: 1 — epididymis; 2 — convoluted tubules testicles; 3 — straight tubules; 4 — protein shell and membrane; 5 — slice; 6 — twisted tubule (elongated and enlarged); 7 — mature sperm


The epididymis is a coiled tube (in expanded form its length is almost 6 meters), which runs along the back of the testicle. From each of the epididymis vas deferens begins. In the end, they are connected to the ducts of the seminal vesicles and open into the urethra. Here the urinary path is combined with genital (hence is the name — urogenital system). Secrets of accessory genital glands (prostate and seminal vesicles) with sperm form semen or seminal fluid.

  • Determine the relationship of testicle structure and functions.

  • Explain the biological essence of placing testicles not inside but outside the body.

  • What are the features of the epididymis structure and functions?

  • Why the testicle is a mixed gland secretion?