Final - Male Reproductive Flashcards
Describe the flow of sperm through the male reproductive tract.
testis -> epididymis (ductulus efferens -> ductus epididymis) -> vas deferens -> seminal vesicle -> ejaculatory duct -> prostate -> urethra (through penis)
Endocrine function of the testes.
steroidogenesis: synthesize androgens (testosterone by Leydig cells)
Exocrine function of the testes.
spermatogenesis: make sperm (mitosis/meiosis)
Describe overall histo of the testes.
- tubule epithelium with germinal cells
- stroma: dense fibrous CT with septa that form lobules
- Sem. tubules: small lumens with more per space and no apical mods
- tunica albuginea: dense CT capsule
- tunica vasculosa: loose CT with blood vessels
Histological features of the seminiferous tubules.
- complex stratified epithelium (spermatogenic and sertoli cells)
- tunica propria: multilayered CT lacking fibroblasts (myoid cells)
Function of spermatogenic cells.
replicate, mature into cells
Functions of Sertoli cells.
- endocrine fx: FSH & testosterone secreting
- exocrine fx: secretes a protein that binds to androgen, to keep in sperm-making areas
Functions of myoid cells in the seminiferous tubules.
contract to push sperm through tubules
Describe the difference in tubules between mouse and human.
- human: one-stage of development in cross-section
- mouse: multiple in one cross-section
Describe the 3 phases of spermatogenesis.
- spermatagonia: stem cells undergo mitosis, yield committed spermatogonia
- spermatocyte: primary spermatocytes under meiosis, become spermatids
- spermatid: spermatids differentiate into sperm cells through extensive cell remodeling
Describe spermiogenesis (4 stages).
haploid spermatids -> mobile spermatozoa
1. Golgi phase: acrosomal vesicle forms, centrioles migrate
2. Cap phase: acrosomal cap forms over the nucleus and contents condense
3. Acrosome phase: manchette of microtubules forms, mitochondrial sheath forms
4. maturation phase: Sertoli cells phagocytize residual bodies
What is a sperm made up of?
acrosome + nucleus
mitochondrial sheath
tail of microtubules
Describe histo of the tubulus rectus and rete testes
squamous and cuboidal cells - as they move through (towards rete testis)
cells get taller - can have microvilli/cilia
What is the function of the epididymis?
- sperm storage
- maturation (motility and ability to fertilize an ovum)
Describe the histology of the epididymis.
- 2 main sections made of pseudostratified epithelium (ductulus efferens- head, ductus epididymis, has more sterocilia and larger lumen at tail)
- muscle layer: thin towards head and thick towards tail
What are the 2 cell types of the epididymis?
- principal cells (shorter towards tail with sterocilia)
- basal cells (square at base, provide stem cells for replacing principal)
What is the function of the vas deferens?
transports mature sperm from the epididymis to the urethra to prepare for ejaculation
Describe the histology of the vas deferens.
- longest excurrent duct
- 3 layers of smooth muscle
- pseudostratified with stereocilia
What is the function of the seminal vesicles?
- secretory function under testosterone control (how much and how often)
1. fructose (primary substance for sperm metabolism)
2. amino acids
3. prostaglandins
Describe the histology of the seminal vesicles.
- paired, elongated, highly folded tubular glands
- wall: mucosa, thin layer smooth muscle, fibrous coat
- epithelium: pseudostratified (not much cilia)
Function of the prostate?
Secrete (controlled by DHT):
1. acid phosphatase
2. fibrinolysin
3. citric acid
4. prostate-specific antigen (PSA)
Describe the histology of the prostate.
- glands: tubuloalveolar (sacs of glands that secrete in a tube)
- stroma: thick fibromuscular
- parenchyma: mucosa, submucosa, peripheral layer, and simple columnar epithelium
- prostatic concretions: fluid that sits & calicifies
Why is urinary dysfunction a sign of prostate issues?
benign prostate hyperplasia leads to difficulty urinating (transitional zone) and frequent urination with periurethral zone… prostate wraps around ureter so hyperplasia and swelling can lead to dysfunction
What is the bulbourethral gland?
pea-sized glands in urogenital diaphragmW
