Male anatomy Flashcards
What are the two main functions of the testis?
- production of high numbers of spermatozoa (1-25 billion! day) 35,000-200,000/second!
- endocrine gland (=> testosterone)
In what order do the tissues that surround testis go? From inwards out.
Tunica albuginea-> visceral layer of tunica vaginalis-> Cavity of tunica vaginalis -> Parietal layer of tunica vaginalis -> external spermatic fascia-> dartos muscle -> skin.
What is the visceral tunic made of?
Peritoneal cells.
What stuctures comprise the scrotum?
- Parietal vaginal tunic (peritoneum, parietal layer)
- Scrotal fascia
- Tunica dartos (smooth muscle) Scrotum
- Scrotal skin (with sweat glands => cooling)
What do seminiferous tubules produce?
Spermatozoa.
What do leydig cells produce?
Testosterone. They are found in the interstitial space of the seminiferous tubules.
What do sertoli cells do?
Sits on basement membrane and stretches all the way up to where sperm is released in the lumen. They nurse germs cells as they develop from spermatogonium to spermatozoa.
What is the seminiferous tubule composed of?
The tubule is composed of a basement membrane and a seminiferous epithelium (germinal epithlium). The epithelium consisits of a basal compartment and adluminal compartment.
What are sertoli cells anchored to?
Sertoli cells are anchored to the basement membrane and surround the developing population of germ cells. Sperm production starts in the epithelium near the basement membrane.
What 3 parts is the epididymus seperated into and what are their function?
- head (caput): stores sperm until it is ready to undergo maturation. In close association with pampiniform plexus.
- body (corpus: the sperm matures.
- tail (cauda): Storage. The tail, connects to the ductus deferens/vas deferens. Smooth muscle contraction during sexual arousal.
Define epididymal transit time?
Time taken for spermatozoa to travel from the proximal head to the distal tail of the epididymis.
What does the ductus deferens/vase deferens do?
Connects the epididymis (tail) to pelvic urethra.
What does the spermatic cord consist of?
- ductus deferens
- testicular artery and vein (pampiniform plexus)
- nerve and lymphatic supply for testis
What are the three functions of the pampiniform plexus?
- heat exchanger
- pulse pressure eliminator
- transfer of testosterone from testicular vein to artery as there is a high local concentration in testis
What does the tunica dartos do?
-tunica dartos in the smooth muscle in scrotal skin is important for long lasting contraction which reduces surface area and heat loss.
What does the cremaster muscle do?
The cremaster muscle is striated muscle in the spermatic cord that functions for short term elevation of testes.
The left and right testicular artery come of what?
The aorta. Testicular arteries are direct branches of the abdominal aorta.
The left testicular vein drains into where?
Opens into the left renal vein.