Testis Flashcards
Androgens
Male reproductive hormones
species with internal testes
birds
marine mammals
elephant
Identify the testes and describe their normal macroscopic appearance/location across species
location is species specific
Internal
Birds, elephants and seals
External- scrotum
Bull - toward the belly orientated vertically, large
Ram - similar to bull, some breed scrotum covering wool
Stallion - towards the belly , but quite high not as pendulum, orientated horizontally
Boar - scrotum very large diagonal slant pointing out the rear
Canine- towards the belly but more caudal, sometime pendulum, horizontal orientation
Tom - scrotum in the rear close to anus, in a relativity horizontal position.
Describe the macroscopic structure of the testis, including its tissue layers
Should be
Similar size
Moderately firm texture
Regularly shaped (species dependent)
To region
Parenchyma (fxal) and mediastinum (connective)
Explain the structures associated with sperm production
Sperm are produced in the lobules (parenchyma) and exit the testes via the rete testis/tubules
Tissue layers in the testis
Superficial to Deep
Parietal vaginal tunic
Visceral vaginal tunic
Tunica albuginea
The fx of tunica abuginea
Creates the lobules bay meeting in the centre with the mediastinum
What prevent the collars of the lobules
Why are PTV, VTV and TA affected by hormones and neurotransmitters
Because these layers have smooth muscle fibres which help facilitate the sperm moving from the parenchyma to the rete testis
explain the three layer of the scrotum
PVT is looser from the rest and is distinct and thicker
Demonstrating the close attachment of the VVT and the TA
Testicular capsule
VTV + TA
Two parts of the parenchyma
Tubular and interstitial compartments
Tubular = circles Interstitial = the space inbetween has two different cell types only
Explain Stx of seminiferous tubules
2 parts
Seminiferous epithelium (sperm generation)
Lumen (empty space for mature sperm travel to rite testes)
Explain the cell types of seminiferous epithelium
Sertoli cells (somatic support developing sperm)(also called nurse cells)
Immature germ cells (spermatogonia, spermatocytes and spermatids)
Myoid cell make up the lamina propria
Explain the cells of intersitium
-leydig cells (produce hormones)
macrophages (immune cells)
Capillaries
Explain the rete testis
Looks like a big blank space on the histology slide Rete Testis
The rete testis connects the seminiferous tubules to the ductus efferentes. It is lined by ciliated cuboidal epithelial cells that also contain microvilli. The activity of the cilia helps to move the spermatozoa along the tube, as they are immobile until they reach the epididymis. The microvilli absorb excess materials, including protein and potassium, from the seminal fluid.
Explain the whole testis
