This PPT for all Medicos and Non medical Students for better understanding of Testis and their role education purpose only

2. SYNOPSIS
 Introduction to testis
 Embryonic development of testis
 Anatomy
 Scrotum layers
Tunica vaginalis
Tunica albuginea
Tunica vasculosa
 Seminiferous tubules
Spermatogenic cell
Sertoli cell
Leydig cells
 Rete testis
 Efferent ductules
 Testicular arteris
 Summary
 References.

3. TESTIS
 Male gonad.
 Mixed exocrine and
endocrine gland because
they produce sperm and
Secreting male sex
hormones.
 They are contained within
the scrotal sac, which is
located directly behind the
penis and in front of the
anus.

4. EMBRYONIC DEVELOPMENT OF TESTES
 During mammalian development, the gonads are at
first capable of becoming either ovaries or testes.
 week 4, the gonadal rudiments are present within the
intermediate mesoderm adjacent to the developing
kidneys.
 week 6, sex cords develop within the forming testes.

5.  In males, the sex-specific gene SRY that is found on
the Y-chromosome initiates sex determination by
downstream regulation of sex-determining factors,
(such as GATA4, SOX9 and AMH), which leads to
development of the male phenotype.
 first trimester gestation -Testosterone and its potent
derivative, dihydrotestosterone, play key roles in the
formation of male genitalia in the fetus but do not play
a role in the actual formation of the testes.

6.  seventh month of gestation- the testes are formed in
the abdominal cavity and descend into the scrotum, its
stimulated by androgens.
 The production of testosterone by the fetal testes is
stimulated by human chorionic gonadotropin, a
hormone secreted by the placenta.

7. Anatomy:
 Paired, oval gland in the scrotum.
Length = 4-5cm
Diameter = 2.5cm
Mass = 10-15gm(single)
Temperature = 35°c

8. STRUCTURE

9. SCROTUM LAYERS
The scrotum consists of
loose skin and
subcutaneous layers and
supports the testis.
Tunica vaginalis
Tunica albuginea
Tunica vasculosa

10. Tunica vaginalis
 Outer thin ,serous sac .
 Derived from peritoneum.
 Forms during the descent of the testis.
 Partially covers the testes.

11. Tunica albuginea
 Internal to the tunica vaginalis.
 Tough, White fibrous capsule composed of dense irregular
connective tissue called tunica albuginea.
It extents inward
Form septa
Divide testis into serious of internal compartments called
lobules.
Each 200-300 lobules contain 1-3 tightly coiled tubules
called seminiferous tubules(semin-seed,fer-carry).

12. Tunica vasculosa
Testicular artery descends to the inferior pole just deep
to tunica albuginea.

13. Seminiferous tubules
 Each lobules of the testis contain one or
three tightly coiled seminiferous
tubules.
 Uncoiled-70cm in length.
 Functional unit of testis . Because the
spermatogenesis occurs here.
Within the Seminiferous tubules :
Spermatogenic cell:
Here, germ cells develop into
spermatogonia, spermatocytes,
spermatids and spermatozoon through
the process of spermatogenesis.

14. Sertoli cell
 Sertoli cell (a kind of sustentacular cell)
is a 'nurse' cell of the testes that is part of a
seminiferous tubule.
 It is activated by follicle-stimulating
hormone and has FSH-receptor on its
membranes.
 Extend from the basement membrane to
the lumen of the tubule.
 Internal to the basement membrane and
spermatogonia, tight junction joins
neighboring sertoli cells to one another.
 These junction form obstruction known as
blood- testes barrier.

15. EXOCRINE FUNCTIONS:
 Mechanical support.
 Nourishment.
 Phagocytosis of cytoplasmic fragments.
 Release of spermatozoa.
 Blood testis barrier.
ENDOCRINE FUNCTIONS:
 anti-Müllerian hormone (AMH)
inhibin and activin.
androgen binding protein.
Estradiol.
Transferrin.

16. Between tubules (interstitial cells):
Leydig cells :
 cells localized between
seminiferous tubules .
 produce and secrete
testosterone and other
androgens
 sexual development and
puberty,
 secondary sexual
characteristics.
 supporting spermatogenesis.
 Testosterone also controls
testicular volume.

17. Rete testis:
 Once the sperm produced,they move through the
Seminiferous tubules and enter the rete testes for
further maturation.
 Cilia are located on some cells of the rete testis
persumably for moving the sperm.

18. Efferent ductules:
 sperm Transported out of the testis into epididymis
through the series of efferent ductules.
Testicular arteris:
 Arises from the abdominal aorta below the origin of
renal arteris.
 Testis receive blood through the testicular arteris.

19. Summary
It’s a male gonad, paired oval gland in the scrotum.
seventh month of gestation- the testes are formed in
the abdominal cavity and descend into the scrotum, its
stimulated by androgens.
Scrotum layer
Seminiferous tubules.
 Rete testis
 Efferent ductules
 Testicular arteris
Function-spermatogenesis and steroidogenesis.