Male Anatomy and Histo Flashcards
what is the male repro tract designed to do? (4)
-produce sperm
-store sperm
-release sperm
-produce hormones
what do the indifferent gonades develop from?
Develop from thickening of intermediate mesoderm (steroidogenic) – genital/gonadal ridge
what is development of primordial gonads linked with?
Development of primordial gonad linked with degeneration of the
mesonephros
what do primitive sex/gonadal cords develop from?
Primitive sex/gonadal cords – develop from epithelial cells of degenerating mesonephric tubules and glomerular capsules that invade the mesenchyme of genital ridge
what do epithelial cells form?
Epithelial cells form clusters and incorporate PGCs
what is another name for the mesonephric duct
wolffian
what duct degenerates in males and what causes them to disappear?
paramesonephric duct, in the presence of testosterone they degenerate
what is another name for the paramesonephric duct
mullerian
what do mesonephric ducts turn into
Efferent ductules and rete testis form from mesonephric tubules
how do accessory sex glands develop
Accessory sex glands develop as evagination from epithelium of associated ductwork
what do gonadal cords become
Gonadal cords hypertrophy and become seminiferous cords/tubules
what makes up spermatognesis?
Spermatocytogenesis + Spermiogenesis
what type of glands do testicles have
endocrine and exocrine glands
what do type B cells give rise to
primary spermatocytes
what produces type B cells
Type A(p) divide by mitosis to produce type B cells
what do type A(d) cells ensure
These cells replicate to ensure a constant supply of spermatogonia
features of sertoli cells (sustentacolar cells)
- Columnar cells with oval to angular nucleus
- Cytoplasmic processes forming gap junctions
- Surround the developing sperm
what are the hormone producing cells
interstitial cells of leydig
features of leydig interstitial cells
- Species differences in # and morphology
- Cytoplasmic stains eaosinophilic
- EM shows large amount of ER, Golgi, mitochondria and lipid droplets
what do sertoli cells provide and where does a single cell extend
- Provide structural and metabolic support to the developing sperm cells
- A single Sertoli cell extends from the basement membrane to the lumen of the seminiferous tubule
testes are suspended in the scrotum by the ____ ____
spermatic cord
components of the spermatic cord (4)
- Spermatic/testicular artery
- Spermatic veins
- Lymphatics
- Cremaster muscle
what does the pampinoform plexus do
counter current heat exchange between warm arterial blood and cool venus blood -> cools arterial blood before entering testis
components of the epididymis
A single coiled tubule: head (caput), body (corpus), tail (caudae)
what is the epididymis lined by and what does it secrete
- Lined by pseudostratified columnar epithelium
- Secretory cells secreting components required for sperm maturation
histological appearance of the ductus deferens
- Pseudostratified columnar
epithelium - Thick tunica muscularis
- Extensive folds (Ampulla) in
stallion, ruminants, dogs - Ampulla thickened due to accessory glands within wall of vas deferens
what species dont have an ampulla
boars and cats
what are the three parts of the penis and their details
- Root of the penis (radix): the attached part, consisting of the bulb of penis in the middle and the crus of penis, one on either side of the bulb.
- Body of the penis (corpus): dorsal (posterosuperior in the erect penis), and ventral or urethral (facing downwards and backwards in the flaccid penis).
- Epithelium of the penis consists of the shaft skin, the foreskin, and the preputial mucosa on the inside of the foreskin and covering the glan penis
____ tissue enclosing the penile urethra
erectile
two types of penis’
fibroelastic and musculovascular
fibroelastic penis; species with it, amount of different tissues and features
- Bull, boar, ram
- Large amount of CT and elastic fibres
- Limited erectile tissue
- Sigmoid flexure: increase in penile length only during erection
musculovascular penis; species with it, amount of different tissues and features
- Stallion, dog, cat
- Lots of erectile tissue
- Erection results in increase in length and diameter due to cavernous tissue becoming filled with blood
special features of the boar penis
-nonpendulous and inverted testicles (tail of epididymis is above the head of the epididymis)
-cork screw shape
special features of the stallion penis
-vascular penis; bell shaped
-no sigmoid flexure
special features of the ram penis
-filiform appendage
types of erectile tissue
- Corpus Cavernosum: two columns on dorsal side of penis
- Corpus Spongiosum: single column on ventral side of penis, surrounds penile urethra
Functions of Sertoli Cells during
Spermatogenesis (7)
- Maintain the right environment for development and maturation
(blood-testis barrier) - Secrete substances initiating meiosis
- Secrete supporting testicular fluid
- Secrete ABP, which concentrates testosterone in close proximity to the developing gametes
- Secrete hormones affecting pituitary gland control of spermatogenesis (e.g. inhibin)
- Phagocytose residual cytoplasm left over from spermiogenesis
- Protect spermatids from the immune system of the male (blood-
testis barrier)
