MALE REPRODUCTIVE SYSTEM - Consists of testes, ducts, genital glands,
1) Production of spermatozoa by spermatogenesis
2) Production of androgens (male sex hormones)
3) Deposition of spermatozoa into female reproductive tract

TESTIS = situated external to abdominal cavity in scrotal sac; allows reduced
temperature below that of the body core (37oC), this reduced temperature is important
for viability of sperm
- Surrounded by testicular capsule:
1) Outer Layer = Tunica vaginalis - mesothelial lining
2) Middle Layer = Tunica albuginea - fibroelastic CT with smooth muscle cells
3) Inner Layer = Tunica vasculosa - highly vascular areolar CT
- Spermatozoa produced in seminiferous tubules = highly convoluted tubules
grouped by septal extensions of capsule into lobules (contain up to 4 seminiferous
tubules per lobule)
- Seminiferous tubules lined by complex germinal epithelium = highly
modified stratified cuboidal epithelium, underlain by basal lamina and peritubular CT
- Myoid cells in peritubular CT assist in movement of sperm along tubule
- Germinal Epithelium consists of:
1) Spermatogenic Cells: in sequence from basal to lumenal surface =
spermatogonia (2N), Primary Spermatocyte (2 X 2N), Secondary Spermatocyte (2 X 1N),
Spermatid (1N), Spermatozoa (1N)
2) Sertoli Cells = nutritive and supportive cells; extend from base to lumen;
nucleus with prominent nucleolus which distinguishes it from germ cells


3 Types of Spermatogonia are present:
1) Pale Type A = stem cells (renewing cells); ovoid lightly stained nucleus
2) Dark Type A = reserve stem cells; divide infrequently and only if renewing
stem cells become depleted; ovoid darkly staining nucleus
3) Type B = differentiating progenitor cells; spherical nucleus with densely
stained masses of chromatin

Consists of 3 regions:
1) Head
2) Midpiece
3) Tail

- HEAD contains 1N nucleus and is crowned by acrosomal cap = contains hydrolytic
enzymes for penetrating egg surface
- MIDPIECE forms base of tail and is surrounded by a small amount of cytoplasm that is
rich in mitochondria (mitochondrial sheath), provides energy for swimming
- TAIL is a flagellum, allows motility

- Between seminiferous tubules is areolar CT (interstitial tissue) containing
Leydig Cells = large polyhedral or ovoid cells, contain pale acidophilic cytoplasm
that may appear vacuolated and a round dark-staining nucleus, Leydig cells are
closely associated with capillaries, secrete testosterone

1. Rete Testis = anastomosing network of tubules extending from apex of
testicular lobules to vas efferens
- lined by simple cuboidal or squamous epithelium with one cilium per cell
- underlain by basal lamina and vascular CT
2. Vas Efferens = convoluted tubes emptying into epididymis (10-15 total)
- simple columnar epithelium (ciliated) with interspersed cuboidal cells
- surrounded by a thin band of circular smooth muscle
- microvilli on lumenal surface, epithelial cells absorb much of the fluid produced in
seminiferous tubules
3. Epididymal Duct = efferent ductules merge to form a single duct
- tortuous path, acts as a long storage duct where sperm acquire motility
- lined by a PSC with stereocilia, active in secretion/reabsorption
- epithelium underlain by a thin lamina propria and a circular layer of smooth muscle;
at its extreme lower end has inner longitudinal, middle circular and outer
longitudinal layers; at upper end, peristaltic contractions move sperm to storage in lower end
4. Vas Deferens = ductus deferens = muscular-walled duct (3 layers); thick
middle circular layer - peristaltic contractions transport sperm to urethra (emission)
- lined by PSC with fibroelastic lamina propria, stereociliated except at lower end
- longitudinal folds are present in mucosa
- divided into: 5. Ejaculatory Duct = formed by merging of vas deferens and excretory duct of
seminal vesicle



1. Seminal Vesicles = tortuous glandular diverticulum that empties into
ejaculatory duct, secretes a viscous liquid contributing to semen
- epithelium is usually PSC but may be simple columnar
- dependent on testosterone for glandular activity
- mucosa is highly folded, surrounded by a smooth muscle coat (inner circular, outer
longitudinal) and elastic adventitia

2. Prostate Gland = surrounds urethra at its origin
- actually is an aggregate of 30-50 compound tubuloalveolar glands
- arranged in 3 layers:
a) small mucosal glands
b) larger submucosal glands
c) large main prostatic glands toward periphery of gland
- surrounded by fibroelastic capsule, glandular material embedded in fibroelastic
stroma with smooth muscle fibers
- lined by PSC or simple columnar/cuboidal
- secretes serous fluid that is rich in proteolytic enzymes that aid in liquification of
semen; secretory state is dependent on testosterone
- in older glands, concretions may develop - represent condensation of secretions

3. Bulbourethral Glands = paired glands, empty into urethra
- compound tubuloalveolar
- surrounded by a thin CT capsule inside a skeletal muscle layer, septa from capsule
divide the gland into lobules
- simple cuboidal to columnar glandular epithelium
- secrete viscous mucous secretion acting as a lubricant for urethra

- composed of erectile tissue arranged into 3 columns bound to one another and
surrounded by areolar CT and thin skin on outside
1) paired corpora cavernosa dorsally
2) single corpus spongiosum surrounding urethra
- erectile tissue consists of irregular vascular spaces separated by dense fibroelastic CT and smooth muscle
- possesses a rich nervous supply; parasympathetic stimulation results in relaxations of
arterial walls leading to engorgement of vascular spaces with blood = erection