Module 6-spermatogenesis Flashcards
what male mammal lacks the Y chromosome and sry gene
amami spiny rat
what activates sox9 in amami spiny rat
two copies of the enhancer Enh14
what is DNA wrapped around in sperm
protamines
four stages of spermatogenesis
spermatocytogenesis
meiosis
spermiogenesis
spermiation
spermatocytogenesis
mitosis phase(proliferation)
meiosis stage
in 2 stages
DNA crossover
spermiogenesis
differentiation. final maturation phase(from round shape to sperm shape)
spermiation
release of sperm into lumen of seminiferous tubules
what part of spermatogenesis occurs in basal membrane
proliferation
what part of spermatogenesis occurs in adluminal membrane
meiosis
differentiation
what hormone does the basal membrane require
LH
Testosterone
what hormone does the adluminal membrane require
FSH
stem cell renewal
-some maturing sperm cells revert back to the starting point
-allows for continued sperm production
what is the theoretical yield of sperm from one spermatogonium
256
where does most sperm loss occur during sperm production
mitotic spermatocytogenesis phase
phases of differentiation(Spermiogenesis)
Golgi phase
Cap phase
Acrosome phase
Maturation phase
Golgi phase
-golgi condenses to form proacrosomal granules that give rise to acrosome.
-centrioles migrate from the top of nucleus to the bottom
Cap phase
-acrosome forms a cap on the nucleus
-remaining Golgi migrates downward with cytoplasm
-distal centriole connects to proximal centriole to form axoneme(cytoskeleton of sperm tail)
acrosomal phase
-cytoplasm continues to pull downwards
-PC forms neck region
-DC continues to elongate
-Manchette anchor acrosome to keep on the sperm head
Maturation phase
-manchette attach to neck to anchor acrosome
-mitochondria condense below neck piece(middle piece)
T/F the time it takes for spermatogenesis is fixed and constant
TRUE
how often do stem cells enter spermatogenesis in men
every 16 days
how often do stem cells enter spermatogenesis in bulls
every 13.5 day
cycle definition
progression through sequence of all stages
stage definition
specific cellular associations
how long is a bulls spermatogenic cycle
13.5 days
how long is a rams spermatogenic cycle
10.1 days
how long is a boars spermatogenic cycle
8.3 days
how long is a stallions spermatogenic cycle
12.2 days
how long is a rabbits spermatogenic cycle
11 days
how many cycles does it take to complete spermatogenesis
4.5 cycles
waves definition
the sequential order of stages happening along the seminiferous tubule
what did the 2002 study determine was the purpose of hooked sperm in mice
sperm lock together to swim faster
did the 2013 Australian study on mice sperm agree or disagree with the 2002 study
disagree. it said sperm swam faster by themselves
what did the 2021 study determine about the hook on mice sperm
sperm clumping in polygamous sperm swim faster than monogamous sperm
where is there a high degree of disulfide crosslinking
tail of the epididymis
disulfide crosslinking definition
formation of tight bonds to further compact DNA
fate of unejaculated sperm
reabsorption
disposal in urine
function of accessory fluid
transport sperm
energy source(fructose)
buffer
places for variation in amount of sperm production
testes size
efficiency of spermatogenesis
number of Sertoli cells
length of spermatogenesis
what information does CASA give you
motility
morphology analysis
what does CASA stand for
computer assisted semen analysis
motility definition
-velocity
-linearity
morphology analysis definition
area of sperm head
acrosome
vitality(living or not)
sperm head abnormalities
crater defect
tapered head
ruffled acrosome
knobbed acrosome
sperm tail abnormalities
coiled tail
double midpiece
folded tail
detached head
steps for sex-sorted semen
-vital dye absorbed by DNA(X absorbs more than Y)
-laser pings off fluorescent dye
-detector reads absorption
-droplet charging collar assigns charge based on absorption
-magnet field directs sperm to containers
spermatogonia
-closest to basement membrane
-divide during prolifereation
primary spermatocyte
product after mitosis phase completion
secondary spermatocyte
product after meiosis I
spermatid
product after meiosis II
Spermatozoa
product after being released into lumen of seminiferous tubule
postnuclear cap
forms from manchette that attach to acrosome and neck region of sperm
what organelle forms the axoneme
distal centriole
what microtubule-based cytoskeletal structure forms the flagellum
axoneme
what mechanism allows for some spermatogonia to revert back to provide continual production
stem cell renewal
what hormone is responsible for negative feedback in leydig cells
testosterone
what hormone is responsible for negative feedback in sertoli cells
inhibin
what glycoprotein is produced by sertoli cells in response to FSH and binds to testosterone and DHT
androgen binding protein
name of vital dye used for sex sorted semen
flourochrome
