Reproductive: Spermatogenesis Flashcards
Where does spermatogenesis occur?
between the seminiferous tubules and Sertoli cells
Where are the Sertoli cells located and what separates them?
extend between seminiferous tubule basement membrane to lumen and separated by tight junctions => blood testis barrier and germ cells
What is the function of the blood testis barrier?
protects spermatocytes and spermatids from immune system
What are the 3 stages of spermatogenesis?
- Spermatocytogenesis;
- Meiosis;
- Spermiogenesis
Where does spermatocytogenesis begin?
at puberty adjacent to basement membrane of Sertoli cell
What is first to undergo spermatocytogenesis? what is the process?
spermatogonia mitotically divide into spermatocytes
What is the process of meiosis for?
reduces diploid spermatocytes into haploid spermatids
Define the final step of spermatogenesis
Spermiogenesis => maturation of spermatids into mature spermatozoa
What occurs to the DNA during spermiogenesis? what is this result?
spermatids undergo chromatin condensation and nuclear elongation =>forms head of spermatozoa
Define acrosome and when it occurs
hydrolytic enzyme containing region on the sperm cell head that forms during spermiogenesis
How does the sperm move?
mitochondrial sheath in midpiece of sperm contains DNA for the flagellum to propel sperm forward
What does the flagellum contain?
array of 9+2 microtubular pairs of linked dynein arms
An absent or defect in the dynein arms results in what disease?
Kartagener’s syndrome
How might patients with Kartagener’s syndrome present?
bronchiectasis from reduced mucus clearance in respiratory pathways along with reduced sperm motility
Once the spermatozoa detach from sertoli cells, what is the next step?
combines with fluid that aids in movement of spermatozoa into epididymis
