Spermatogenesis, Testis and Epididymis Flashcards
What is spermatogenesis? And what are the three phases it consists of?
The process whereby spermatozoa are formed – proliferation (mitosis), meiosis & differentiation
• What types of spermatogonia are formed in the proliferation stage?
A spermatogonia -> spermatogonia B -> spermatogonia
What is the product of the meiosis phase?
Primary spermatocytes ->secondary spermatocytes
What is the function of differentiation?
Conversion of spermatids into spermatozoa
What is the function of the intercellular bridges?
Connect the spermatids enabling a synchronous development of a generation of cells (structure is that of a syncytium)
Why is the lifespan of a primary spermatocyte longer than that of any other germ cell found in the seminiferous epithelium?
Because prophase of the first meiotic division is a relatively long process
What are the four phases of the differentiation phase?
Golgi phase, cap phase, acrosomal phase, maturation phase
What are the sections of a spermatozoa tail?
Capitulum, middle piece, principle piece, terminal piece
Where are immature cells found in the seminiferous tubule?
In the basal component
At which stage is sperm released?
Stage VIII
How long does it take for one cell to complete spermatogenesis?
4.5 cycles
What is the stage? What is the cycle?
Stage – specific cellular associations at any cross section at any moment in time
Cycle – progression through sequence of all stages
Which hormones is spermatogenesis dependent on the production of?
GnRH, FSH, LH, testosterone & oestrogen
What are the functions of LH and FSH?
• LH – binds to leydig cells, stimulates production of testosterone
FSH – binds to sertoli cells, stimulates conversion of testosterone to dihydrotestosterone and the production of inhibin & estradiol
What is the stimulus for spermatogenesis?
High concentrations of testosterone in the testes
