Male Flashcards
Describe the structure of the testes from outer to inner
- Scrotum - with dartos muscle which darkens and crinkles skin
- External spermatic fascia
- Cremaster muscle - raises testis when cold to protect
- Cremasteric fascia
- Internal spermatic fascia
- Tunical Vaginalis - parietal and visceral layers
- Tunica albuiginea
Describe the passage of sperm from the location of production out of the penis
- Produces in coiled seminiferous tubules
- Tubule rectus
- Rete Testis
- Efferent ductules
- epididiymis
- ductus deferens
- seminal vesicles
- ejaculatory duct
- Prostatic Urethra through prostate
- Membranous Urethra
- Penile Urethra
What is the epithelial lining of the epididymis?
pseudostratified columnar epithelium with stereocilia
How does sperm travel through ductus deferens?
Peristalsis
Where are the Seminal vesicles and what is their function?
- Outpouchings of ductus deferens
- secrete alkaline viscous fluid - neutralise female acidic conditions
- Fructose - ATP production by sperm
- Prostaglandins - aid sperm motility
How is the ejaculatory duct formed?
Seminal vesicles joining with ductus deferens on either side
What is the function of prostate gland?
- Citrate (ATP production)
- Acid phosphatases - proteolytic enzymes to liquefy coagulated semen
What is the function of the bulbo-urethral glands
Produces Mucous-like secretion into spongy urethra
Where are sertoli cells located and what is their function?
- Located in seminiferous tubules
- support spermatogenesis by nourishing spermatocytes, spermatids and sperm, phagocytose excess spermatid cytoplasm, produce fluid for transport, secrete inhibin, regulate effects of testosterone and FSH
Where are leydig cells located and what is their function?
- Located in the spaces between seminifirous tubules
- produce testosterone - controls sperm production and male characteristics
When does spermatogenesis begin and stop?
Begins at puberty and continues until death
Describe the process of spermatogenesis
- Dark type A Spermatagonia divide threough mitosis to produce dark A and Pale A
- Pale A mature into Type B
- Type B diffrentiate into primary spermatocytes
- Primary spermatocytes undergo DNA replication and enter meiosis I to produce secondary spermatocytes (these are haploid but contain pair of chromatids)
- Secondary spermatocytes undergo meiosis II to produce round spermatids
- Round spermatids under spermiogenesis to differentiate into elongated spermatids
- Residual bodies are lost from these, producing final spermatazoa
Describe the role of regulatory hormones in spermatogenesis
GnRH causes release of FSH and LF from anterior pituitary.
FSH causes sertoli cells to undero spermatogenesis, and also produce inhibin to negatively feedback on FSH production
LH causes Leydig cells to produce testosterone to stimulae sertoli cells for spermatogenesis, negatively feedback on LH production and also play a role in the developmetn and function of secondary sex characteristics, prostate gland and seminal vesicles
How can phthalates cause reproductive problems?
man-made chemicals which when consumed in high levels during pregnancy, can:
- decrease testosterone production
- reduce Insl3 production - required for testicular descent
- cause abnormal testis development
- postnatally can cause testicular dysgenesis syndrome
What abnormalities are associated with testicular dysgenesis syndrome
Testes not developed properly causing problems with:
- sertoli cells - infertility and TGCC
- leydig cells - cryptorchidism and hypospadias
