Male Reproductive System organs that function in: gamete and hormone production not all in abdominal cavity paired testicles = controlled by LH & FSH duct systems accessory glands
Testis: Gross Histology - from Latin for witness - production of spermatozoa & testosterone - serosa - tunica albuginea = capsule - mediastinum with rete testis - fibrous septae = 300 lobuli testis - contain 1-4 convoluted tubules - tunica vasculosa - unlike ovaries continuous production
Seminiferous Tubules - enclosed in basal lamina & muscle - seminiferous epithelium - 2 cell types: spermatogenic Sertoli - degeneration in Klinefelter s patients = XXY - small testicles, reduced fertility - high gonadotrophins, low testosterone - gestational age of 18-22 weeks - reduced germ cells, regular supporting cells
Spermatogenic Cells Spermatogonia - stem cells for sperm production - mitotically active - type A= new spermatogonia - type B = spermatocytes, not stem cells Primary spermatocytes - larger than spermatogonia - always visible in human testis - complete meiosis 1 Secondary spermatocytes - rarely visible in human testis Spermatids - luminal - small w/ dark nucleus - nucleus condenses
Spermatogenesis - process of development from spermatogonia to sperm - in testis/epididymis - 64 days - starts at puberty - death - distinct stages: Spermatotcytogenesis - gonial - 1 spermatocytes - diploid chromosomes Spermatidogenesis - 1 & 2 spermatocyte (diploid and haploid) - final product = spermatid Spermiogenesis - maturation into spermatozoa
Spermiogenesis Golgi phase - spermatids develop polarity - head formation - Golgi = acrosome - other end = thickened piece - axoneme formation - DNA packaged/ condensed Cap phase - Golgi surrounds nucleus Acrosomal phase - centriole elongates - sperm orientation = lumen Maturation phase - phagocytosis of cytoplasm by Sertoli cells
Mature Spermatozoa - head flattened, 5!m long 3!m wide - 2/3 covered by acrosome = fertilization - short neck with 1 transvers centriole - tail = axonema (microtubular arrangement) end piece (small cytoplasm) - different head shape
Supporting Cells of the Testes Sertoli cells - evenly distributed, columnar with processes - ovoid/ angular nucleus - mechanical/nutritive support - activated by FSH (receptor on surface) - secrete inhibin and activin Interstitial cells of Leydig - 15-20!m, in interstitial tissue - endocrine = testosterone - clusters of variable size - cytoplasm acidophilic - large, eccentric nucleus
Epididymus - tubuli recti (columnar)-rete testis (squamous/cuboidal)- ductus efferentes (columnar)- epididymus (PSCCE) - 6 m long - epithelium w/ stereocilia - divided into principal and basal cells - basal lamina - smooth muscle = no spontaneous contraction - functional maturation of spermatozoa = mobility
Vas deferens = ductus deferens - ontinuation of epididymis - 35-40 cm long - ending in seminal vesicle to form ejaculatory duct (through prostrate) into urethra - mucosa = PSCCE, stereocilia lamina propria - muscularis = 1.5 mm thick, well developed middle circular, outer/inner longitudinal - adventitia = loose CT, blood vessels & nerves other functionality vasectomy
Prostate - chestnut size, weighs 20g - 30-50 tuboalveolar glands = open into urethra - anterior, lateral, posterior lobe - PSCCE with basal & secretory - secretory = acidophilic - changes near urethra - luminar extesion = product - first fraction of ejaculate - corpora amylacea = rounded, acidophilic body - glands embedded in fibromuscular stroma - age = enlarged prostrate (45)
Seminal Vesicle - paired diverticula of vas deferens - 2 cm wide, 4 cm long - convoluted tubosaccular glands - secretes significant portion of semen - secretion: sperm coagulum sperm motility female immune suppression mucosa = - elaborate folding (honeycomb) - PSCCE or columnar - lamina propria = loose CT w/ elastic fibers lumen = secretory product muscularis = inner circular/ outer longitudinal
Penis 3 cylindrical bodies Paired corpora cavernosum Corpus spongiosum = erectile bodies Urethra Tunica albuginea Sensory nerve endings, Paccinian corpuscles Stratified columnar to stratified squamous Glands of Littre