Reproduction - male Flashcards
Name two layers of the testes
- Tunica vagnalis - sac-like extensions of peritoneum, descends into scrotum with testes (outer layer), flattened mesothelial cells
- Tunica albunginea - the white fibrous capsule, collagen
- Tunica Vasculosa - loose connective tissue containing blood vessels and lymphatics
Name the type of spermatid daughter cells in the testis, what do they do?
Type A - remain outside of blood-testes barrier (BTB), they produce daughter cells until they die (dark nuceli)
Type B - these differentiate into primary spermatocytes cells, they then pass through the BTB and move towards the lumen of the testes
Meiosis I then occurs - producing two secondary spermatocytes
Meiosis II then produces 4 spermatids
These spermatids sprout a tail and discard cytoplasm
What occurs in the epididymus?
Site of sperm maturation and storage
Describe the passage of the sperm (SEVEN UP)
S - SEMINIFEROUS TUBULES in the testes (Tubuli recti connect to Rete Testis, then efferent ducts and the epididymis)
E - EPIDIDYMUS
V - VAS DEFERENES (vas and efferent duct join to form ejuact.duct)
E - EJUACTULATORY DUCT
(N)
U - URETHRA
P - PENUS
What are the two cell types in the testis?
- Sertoli cells (produce sperm) - form blood-testes-barrier
- Columnar cells
- Phagocyotic, protective, supportive - Leydig cells (produce testosterone), large amounts of SER (to produce hormone)
contain Reinke’s crystals (no known function, useful to identify)
Describe the differentiation of spermatogonia and describe the nucleus at each stage
- Spermatogenia (type A and B) - uniform nucleus
- Spermatocyte - speckled nucleus (primary 2n, to secondary n)
- Spermatid - dense nucleus
- Spermatozoon - oval nucleus, mature haploid cell
Describe the axoneme of sperm
- Dynein arms act in a similar way to troponin in muscle
- 9 +2 arrangement of microtubules (one complete and one partial membrane)
What occurs in the Rete Testis?
(Seminiferous tubules to Tubuli recti to Rete testis to efferent ducts)
- Fluid reabsorption occurs in the rete testis so that the spermatozoa is concentrated
- Cuboidal epi, microvili and cilia
What are stereocilia? Where are they found?
Stereocilia have long projections, immotile (unlike cilia - this means fluid volume propels along)
- Aid absorption
- Found on epididymis, efferent tubules and van deferenes
What occurs in epididymus?
- Sperm enter the head imotile and leave two weeks later from tail motile :)
- Has head, body and tail
- Reabsorbs seminiferous tubule fluid
- pseudo stratified
- sterocilia
- muscle has no peristaltic motion
Describe the vas deferens
- 30-40cm tubule
- pseudo stratified columnar
- thick 3 layered muscular wall = peristalic motion
- Vas joins the efferent duct to form the ejaculatory duct within the prostate
What is the cremaster muscle?
Covers the testes and the spermatic cord
Describe the prostate and its function
- Stroma
- Smooth muscle
- Fibro-elastic fibres
- Secretes alkaline fluid to neutralise acidic environment of female genital tract
- Connective tissue
- 30-50 tubuloalveolar glands with ducts
- Combines with seminal vesicle
- Periurethral mucosal glands
- Periurethral submucosal glands
What do seminal vesicles produce?
Produces 50% volume of fluid for ejaculate
- Empties into ejaculatory duct
- Psuedostrat columnar
What do Cowper’s (bulbourethral) glands produce?
Lubricating mucus, empties into post-prostatic urethra