reproduction; oogenesis + spermatogenesis Flashcards
(41 cards)
what is spermatogenesis? where does it take place
process is called during gamete formation, ending with 4 haploid sperm cells
takes place in the testes»seminiferous tubules of male
what does sperm cell end with with its four non identical haploid cells?
have the same number of chromosomes and an equal amount of cytoplasm.
what do each tubule have beneath the enclosed membrane
Each tubule is enclosed in basement membrane» beneath is a layer of germinal epithelium cells/ spermatogonia
germinal epithelium cells
diploid cells that divide (mitosis) regularly which produces more diploids that enlarge, known as: primary spermatocytes
primary spermatocytes divide by
meiosis
primary spermatocytes first division
first neurotic division produce two haploid cell»_space; secondary spermatocytes
primary->secondary spermatocyte second division
secondary spermatocytes produce»_space; four spermatids
sperm dvlpt 1– Sertoli cells
what spermatids attach to, also called nurse cells
assist in differentiation of immature spermatids-> spermatozoa by providing n o u r i s h m e n t
sperm dvlpt 2– what happen when spermatozoa develop tail
once spermatozoa develops their tail, they detach from Sertoli cells and carried down the lumen of tubule—> epididymis
testes
are each testis housed outside abdominal cavity in a sac called the scrotum
testes+scrotum = testicles
how does scrotum need to condition itself to procure sperm?
sperm can’t optimally develop at human body temperature, so it remains 2 degrees cooler
makes muscles around the scrotum to contract pulling testes toward the body.
Sperm is controlled by three hormones
follicule-stimulating hormone (fsh)
testosterones
luteinizing hormone (lh)
fsh male
stimulates meiosis in spermatocytes to produce haploid cells
produce by pituitary gland
testosterones
stimulates maturation of secondary spermatocytes into mature sperm cells
produced by testes (signaled to be made by pituitary gland)
lh male
stimulates the secretion of testosterones by the testes
produced by pituitary glands
What stage is sperm created
puberty stage
how do sperm cells leave epididymis? I
sperm cells are released during ejaculation within a nutrient-rich fluid: semen
semen is mixed with sperm cells as they leave epidiymis
leaves to vas deferens via muscular contractions that propel sperm there
ejaculation
expulsion of semen from penis
vas deferens
A duct that passes upward the abdomen and loops around the urinary bladder which joins a short duct: seminal vesicle
the two ducts unite»_space; ejaculatory duct
what is semen produced by
two seminal vesicles and prostate gland
70% of semen fluid from seminal vesicles is made of what?
70% of semen fluid from the seminal vesicles are rich in fructose» provides energy for sperm to swim and contains mucus to protect the spermatozoa from acidic environment of vagina
prostate gland produces
+bulbourethral glands
alkaline gland»_space; thin fluid that further nourishes the sperm
bulbourethral glands» secretes a clear alkaline mucus
oogenesis 1
gamete formation starts will diploid cells: oogonia/germinal epithelial cells with
o v a r i e s
og 2– what occurs when oogonia divides?
oogonia divides by mitosis and enlarges to form primary oocytes