The testes are oval organs that are 4-5 cm in length, 2-3 cm in breadth, and weigh about 10-15 grams each. They are protected by the scrotum and contain seminiferous tubules where spermatogenesis occurs. The epididymis is a coiled tube that receives sperm from the vas efferens and stores it before releasing it to the vas deferens. The vas deferens carries sperm from the epididymis to the ejaculatory duct to be ejaculated via the urethra. Leydig cells in the testes produce androgens that are important for male reproduction.

1. TESTES
(MALE REPRODUCTIVE SYSTEM)
PART- I
Dr R. K. Upadhyay
KV, 39 GTC, Varanasi Cantt

2. Testis
• L= 4-5 cm
• B= 2-3 cm
• Thickness = 2.4 cm
• Weight – about 10- 15 g each
• Contain tough fibrous layers -
i- tunica albuginea –outer
ii- tunica vaginalis
Iii- tunica vasculosa - inner
inside contains testicular lobules.
• Situated inside scrotum.

3. SCROTUM
• Acts as thermo regulator
• Maintain temperature in
testis 2-2.5 o
C
• Protect sperm from high
body temperature
• Failure of the testis to
descend in to scrotum
causes sterility because
spermatogenesis can be
completed at abdominal
temp.

4. Inside testis
• Testicular
lobules – 200-
300
• Each lobule
contain 1-4
seminiferous
tubules
• ST (about 70 cm)
is main site for
spermatogenesis
.

6. EPIDIDYMIS
• LONG TUBE (6 mtr)
• Highly coiled and tightly packed
• Attached to testis
• Receives VE and releases its secretions to VD
• Epididymis stores sperms for some time
• It shows peristaltic contraction at intervals to push
sperm away from testis.

7. Comparisons
VE
• Arise from RT
• 15- 20 number
• Convoluted
• Carry sper from RT to Cauda
epididymis part
VD
• Arise from Cauda epididymis
• 2 in number
• Thick , slightly coiled in scrotum
and staight in abdomen
• Carry sperm from CE to
ejaculatory duct

8. ST
• ST are long (about 70 cm). It is main site for
spermatogenesis.
• STs joins to form tubuli recti.
• seminiferous tubule has two types of cells-
• 1- male germ cells (spermatogonia) and
• 2- Sertoli cells
• The male germ cells undergo meiotic divisions to
form sperm
• Sertoli cells provide nutrition to the germ cells

11. interstitial cells or Leydig cells
• The regions outside the seminiferous tubules called
interstitial spaces
• interstitial spaces contain small blood vessels and
interstitial cells or Leydig cells
• Leydig cells synthesise and secrete testicular
hormones called androgens

12. Testicular
lobule
ST RT VE ED VD

13. ST
RT
VE
EPIDEDYMIS
VD
ED
URETHRA