Histology of the male reproductive tract

Question 1

Formation of haploid sperm

Answer 1

• Occurs in the testicle
  
  • Sperm is formed in the seminiferous tubule (spermatogensis)
    
    • Process of maturation of the sperm happens from the outside to the inside of the seminiferous tubules
      
      • Diploids spermatogonium are found closest to the interstitium
      • These become primary spermatocytes, then secondary spermatocytes and then the haploid spermatid is found at the centre of the seminiferous tubule
      • These are then transferred through the lumen
    • Leydig cells are found surrounding the seminiferous tubules in the interstitium
      
      • Produce testosterone to promote spermaturation

Question 2

formation of sperms from spermatogonia

Answer 2

1. Spermatogonia (2N, 2C)- found towards the edge of the seminiferous tubule
2. Spermatogonia replicates genetic info and moves towards the interior- primary spermatocyte (2N, 4C)
3. Primary spermatocye is sandwhich between adjacent Sertoli cells and are separated by from the exterior of the tube by tight junctions
   
   1. Tight junctions between Sertoli cells help to form the blood testis barrier
   2. To prevent autodestruction of gametes
4. Primary spermatocyte à secondary spermatocytes- meosisis 1
   
   1. 1N, 2C
5. Secondary spermacotcye undergo meosisiss 2 forming haploid spermatid (1N, 1C)
6. Haploid spermatids undergo final maturation
7. Sperms are transported out of the testes via the epididymis

Question 3

Epididymis histology

Answer 3

• Lined by pseudostratified epithelium- with stereocilia
• Where maturation of the spermatid occurs- holding place for later release
• During sexual stimulation the sperm are called upon and travel through the remainder of the tract to the exterior of the tract- vas deferens

Question 4

Histology of the vas deferens

Answer 4

• Muscular channel, lined with pseudostratified columnar epithelium, also contains sterocilia
• Smooth muscle contracts to propel sperm forward
• Vas deferens runs just adjacent to the bladder
• Distal ends of the vas deferens are called the seminal vesicles

Question 5

contributions to the sperm from after the epididymis

Answer 5

• Distal ends of the vas deferens are called the seminal vesicles
• Seminal vesicles (found next to the bladder) are coiled tubes lined with columnar cells which produce and secretes seminal fluid
  
  • Major component of semen
• Progressing Sperm then enter the prostate through the ejaculatory duct
• Within the prostate additional secretions are added to the semen, making it sugary and alkaline- nutrition and protection of sperm
• Sperm then passes through the penis prior to leaving the body
  
  • 2 exocrine glands in the proximal urethra that secrete mucous secretions to help lubricate the urethra – bulbourethral glands

Question 6

• Penis contains three longitudinal tissue- cavities for blood to pool
  *

Answer 6

• Corpus spongiosum surrounds the urethra
• Corpus cavernosum becomes engorged with blood during an erection

Question 7

overview of male histology

Answer 7