Lecture 4: Histology of the Male Reproductive System Flashcards
What are the four parts of the male reproductive system?
- Testis-production of spermatozoa and secretion of male sex hormones
- Genital ducts: collect, store and conduct spermatozoa from each testis
- Accessory glands: secrete a NUTRITIVE and LUBRICATING fluid called seminal fluid
- Penis: copulating organ
What is spermiogenesis?
The process by which haploid spermatids are transformed into spermatozoa
Where does spermatogenesis take place?
The pyramidal compartments (lobules)
-empties into rete testis
What are myoid cells?
They have components of smooth muscle; helps sperm propel from seminiferous tubule to rete testis
Lie in the BASAL LAMINA of the seminiferous tubule
Help with spermatogenesis
What are characteristics of Leydig cells?
- Secretes testosterone
2. Has eccentric nuclei
What is the point of cytoplasmic bridges?
To exchange proteins from sperm to sperm (because some sperm only have X while others only have Y)
What is the tunica albuginea?
The dense fibrous capsule the surrounds the testis
Also surrounds the corpus cavernosum/spongiosum
How is testis divided?
By interlobular septa into 250 pyramidal compartment or testicular lobules
Each esticular lobule contiains 1-4 seminiferous tubules
What are seminiferous tubules?
Where spermatozoa are ultimately produced
What lies between seminiferous tubules?
FibroCOLLAGENOUS tissue that contains
1. leydig cells (interstitial cells) 2. fibroblasts 3. collagen 4. blood and lymphatic vessels
What is TEX14? Significance?
A testis-expressed gene for a novel protein that localizes to germ cell intercellular BRIDGES
No TEX14 = no cytoplasmic bridges
Hence TEX14/cytoplasmic bridges = essential for fertility
What happens when you have no intercellular bridges?
You halt the first meiotic division of male spermatogenesis
What is spermatozoa?
The PROPER term for mature sperm
Mature sperm = spermatozoa
Where are spermatogonia located?
CLOSEST to the basal lamina
What are the two types of spermatogonia?
Type A spermatogonia: dark chromatin, dark all over
Type B spermatogonia: condensed chromatin