Spermatogenesis Flashcards
what hormone bind to leydig cells
LH
what hormone binds to sertoli cells
FSH
what makes up the adluminal compartment
- sertoli cells
- developing germ cells
what makes up the basal compartment
- tight junction
- basement membrane
what is another name the tight junction
blood testis barrier
what is the function of tight junction
keeps blood away from the adluminal compartment
BTB
blood testis barrier
what are the two main jobs of the blood testis barrier
- compartmentalizes the ST
- protects the developing male germ cells
what does the male germ cells need protected from
- the outside environment
- autoimmune response
spermatozoa
the actual sperm
spermatids (on figure)
black dots
spermatocytes (on figure)
red dots
spermatogonia (on figure)
blue dots below tight junction
where are the spermatogonia only found
basal compartment
where are sperm cells only located
basal compartment
1 cell divides into 2 identical cells
mitosis
1 cell divides into 4 different cells
meiosis
what needs to happen before mitosis or meiosis can occur
chromosomes need to replicate
2n—>4n—>2n
mitosis
2n—>4n—>2n—>1n
meiosis
what do mitosis and meiosis both make from 2 copies of each chromosome
4 copies of each chromosome
what three things are needed for spermatogenesis
proliferation
meiosis
differentiation
what is proliferation also considered as
mitosis
where does proliferation occur
basal compartment
only spermatogonia
proliferation
spermatocytes—>spermatids
meiosis
where does meiosis occur
adluminal compartment
where is proliferation pushed through
BTB
spermatids—>spermatozoa
differentiation
where does differentiation occur
adluminal compartment at the lumen
what is differentiation
morphological change from spermatid to spermatozoon
what are the four phases to differentiation
- Golgi
- Cap
- Acrosomal
- Maturation
Golgi Phase
acrosome forms
centriole function
responsible for microtubule organization in cytoplasm
what are the steps during the Golgi phase
- start with round spermatid
- vesicles from Golgi fuse
- centrioles move out of way
- formation of proximal and distal centriole
job of proximal centriole
tail attachment point
distal centriole
- axoneme
- slowly unwind to form core of tail
Cap phase
- acrosome spreads over nucleus
- tail is growing
steps to Cap phase
- axoneme forms
- acrosome flattens (coating nucleus)
- outer and inner acrosomal membrane formed
Acrosomal phase
nuclear and cytoplasmic elongation
what does the manchette become
post nuclear cap
steps of acrosomal phase
- nucleus elongates
- acrosome covers nucleus
- manchette formed
- annulus formed
job of annulus
separates mid and principal tail pieces
Maturation phase
- final assembly
- separation of midpiece from rest of tail