Lecture 19 Flashcards
What is the starting point in spermatogenesis
Spermatogonium
Name the 4 steps of spermatogenesis
Spermatogonium
Primary spermatocyte
Secondary spermatocyte
Spermatid
With each mitotic division of spermatic stem cells, what do each daughter cells become
One stays a stem cell to maintain the population
The other becomes a primary spermatocyte and will enter meiosis
What is the starting point of meiotic division
primary spermatocyte
What does the first round of meiosis yield
2 secondary spermatocytes
what chromosomes/chromatids associated with secondary spermatocytes
23 Chromosomes, 46 chromatids
What do secondary spermatocytes divide into
Spermatid
What has 22 autosomal chromosomes plus one X or Y chromosome
Spermatids
What daughter cell stays to become a stem cell
Type A
What daughter cell goes into meiosis
Type B
What are spermatozoan
More well formed sperm, have the head tail, etc
What is spermiogenesis
Going from spermatid to spermatozoan
What two processes are necessary in spermiogenesis
Reorganization of nucleus and cytoplasm
Development of flagellum
Spermatids and spermatocytes at various stages are embedded in what cells
Sertoli
Where do sertoli cells sit
On basement membrane
What two compartments do tight junctions create
Basal compartment
Adluminal compartment
All stages after initiation of meiosis occur in what type of environment
Avascular
What creates the avascular environment
Tight junctions create a blood-testes barrier
Name 5 things sertoli cells do
Nourish developing spermatozoa
Secrete fluid into seminiferous tubule lumen
Digest cytoplasm discarded by spermatozoa
bind FSH and testosterone
Produce inhibin
Where are the leydig cells
Between the seminiferous tubules
Why is it important for Leydig cells to be vascularized
Because they secrete testosterone and it can get into the blood stream
How long does sperm spend in the epididymis
20 days
What are PGs
Prostaglandins
What is the internal genitalia of the female reproductive system
Ovaries
What are the femal accessory ducts
Uterine tubes
Uterus
Vagina
What is the external female genitalia
Vulva
What are the ovaries anchored by
Ligaments
What is the source of GnRH
Hypothalamus
What is the role of GnRH
Makes anterior pituitary release FSH and LH
What is the source of FSH
Anterior pituitary
What is the source of LH
Anterior pituitary
What is the role of FSH
indirectly stimulates spermatogenesis by making sustenocytes release ABP which keeps local testosterone levels high
What is the role of LH
stimulates Leydig cells to secrete testosterone
what is the source of testosterone
Leydig cells
what is the role of testosterone
stimulate maturation of sex organs, maintenance of secondary sex characteristics, libido
what is the souce of inhibin
Sertoli cells