Reproduction and Development Flashcards
gonads
where gametes are made
male gonad
testes
female gonad
ovaries
where are testes contained?
in the scrotum
cremaster muscle
contracts to draw in testes when cold
Leydig cells
produce testerone
epididymis
sperm mature here and gain ability to move
seminal vesicles
generate nutrients for semen
cowper’s gland
produces pre-ejaculate to neutralize and lubricate uretha
path sperm travels
SEVEN UP
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seminferous tubules
epididymis
vas deferens
ejaculatory ducts
nothing
uretha
penis
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semen
not the same as sperm!
alkaline transporting fluid
endometrium
changes thickness during menstrual cycle in anticipation of implantation
general steps of spermatogenesis
mitosis meiosis I meiosis II spermatid sperm
general steps of oogenesis
mitosis
primary oocyte is arrested in prophase I until puberty
meiosis I (one cell dies)
meiosis II is completed only with fertilization
one cells dies and other becomes 2n zygote
How does sperm enter the egg?
has to use an acrosome reaction to enter the zona pellucida
How does the egg prevent other sperm from attaching?
releases cortical granules
blastocyst
fluid filled cavity with outer layer that will become the placenta and inner layer will develop into the fetus
eptopic pregnancy
blastocyst does not implant itself in the uterine endometrium
gastrulation
formation of 3 germ layers
endoderm
urinary, digestion and respiratory tracts
mesoderm
muscles, connective tissue, bone, circulatory system, kidneys, gonads
ectoderm
nervous system and external structures
nerulation
early formation of neural system
How does the neural tube form?
the neural plate flolds
Androgens
the class of hormones that testosterone is in
secondary sex characteristics
refer to traits not directly involved in reproduction
What hormone levels rise during pregnancy?
hCG, progesterone and estrogen
hCG
maintains corpus luteum during pregnancy to produce estrogen and progesterone
LH in males
stimulates Leydig cells to produce testosterone
FSH in males
promotes spermatogenesis
Three stages of the ovarian cycle
1) follicle matures during follicular phase
2) egg is released during ovulation
3) follicle is transformed into corpus luteum during luteal phase
Ovarian follicle
A small, fluid-filled sac in the ovary that contains one immature egg
Four stages of the uterine cycle
1) menstruation occurs
2) estrogen levels rise
3) proliferative phase where endometrium bulks up
4) secretory phase which overlaps with luteal and endometrium continues to grow
When do FSH levels rise during ovarian cycle?
follicular phase
What do rising estrogen levels allow for?
stimulates the development of the uterine endometrium
What triggers ovulation?
LH
What causes a rise in LH?
a rise in estrogen levels
progesterone and the endometrium
during the luteal phase, endometrium is maintained by progesterone
If hCG is present and corpus luteum is maintained, what happens to LH?
progesterone stops the production of LH so there is no more ovulation
Which hormone is secreted if the ovum is fertilized?
hCG
