reproduction Flashcards
What are the divisions in spermatogenesis? How many N at each stage?
PGC -2N spermatogonia A -2N spermatogonia B -2N primary spermatocyte - 2N secondary spermatocyte -N round spermatid -N elongated spermatid - N spermatazoa -N
When does spermatogenesis occur in males? Which life stage?
post puberty.
What are the divisions in oogenesis? How many N at each stage?
When do these occur in a female? Life stages?
When are polar bodies excluded?
PGC -2n oogonia - 2n primary oocyte -2n - pre birth - pro I secondary oocyte -n - polar body - metII until ovulation. mature oocyte -n -polar body.
What is external fertilisation and what living things do this?
What is a good example of external fertilisation?
outside of the body - aquatic animals - fish.
What is internal fertilisation and what living things do this?
.sperm deposited directly inside usually female - nearly all mammals.
What is urchin reproductive strategy similar to? Why is it so easy to study them?
most mammals - they can be stimulated in lab to produce eggs and sperm easily.
Draw a sea urchin sperm and label
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Draw a sea urchin oocyte and label
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What happens when the sperm meets the oocyte?
- penetrates cumulus.
- binds to zona pellucida receptors causing acrosome reaction.
- penetrates zona pellucida and fuses with oocyte.
leads to cortical reaction - bona hardening.
What is the function of the acrosome?
contains enzymes used to digest through cumulus and zona pellucida/vitelline layer.
What is the acrosomal process made from? And what is its role?
contains enzymes used to digest through cumulus and zona pellucida/vitelline layer.
How do they avoid polyspermy? What are the problems with polyspermy?
- fast block = electrochemical block via influx of Na - temporary an d for externals only.
- urchin - secretion of a barrier of cortical granules
What is the role of the oocytes cortical granules?
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How is the fertilisation envelope formed? What does it do?
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What is the cortical reaction? How long does it take roughly?
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Sketch a human sperm. How does this differ from the urchin?
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Sketch a human oocyte. How does this differ from urchin?
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Where in the repro tract does fertilisation occur?
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Draw and label a female repro tract? Why is it so difficult for sperm to reach? What is the benefit of this?
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What evidence is there that female tract “selects” sperm?
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What are the steps of human fertilisation?
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Apart from bringing genetic material, what other role does sperm have in fertilisation?
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What is the role of sperm-egg recognition?
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What ion is responsible for the fertilisation signal?
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Until what stage in development is reproductive development the same for both sexes?
What arises in this time period?
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What is gene is express after this period? Where is it in the genome?
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What causes female gonad development?
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What happens from week 7 in ovary development? Draw and label what this looks like
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Where do the columns of cells come from?
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How deeply to sex cord penetrate in females? What do they cluster around?
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Where do vasculature and theca cells come from?
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What ducts form the male repro system
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What ducts form the female repro system (think of Muller yogurt – only women eat it)
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Which duct remains in the default pathway?
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When does oogenesis occur?
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Draw a flow chart with the names of the different cells from germ to mature oocyte and spermatozoa. Label when mitosis and meiosis occur.
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When does meiosis occur in males? In females?
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Does complete meiosis occur at once in oogenesis?
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In what stage is meiosis arrested? What is the name of this halt in meiosis?
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When in meiosis 1 completed?
When is the second arrest?
When is meiosis 2 completed?
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At what stage is oogenesis at birth? Spermatogenesis? (in other words which stages occur in utero)
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- What is the female egg number at puberty?
- D
- 22.
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How many eggs will be ovulated in a lifetime?
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Are meiotic divisions symmetrical in oogenesis?
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What is the byproduct of this meiotic division? What is the benefit of releasing these?
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Where do oocytes develop?
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What are the 2 types of somatic cells involved in oocyte development?
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Describe folliculogenesis – the stages?
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Describe the primordial follicle
When do these develop?
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How long from the initiation of follicle development until ovulation? Is this dependent on the menstrual cycle?
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Describe the primary follicle? What do the different cells look like? Is its development dependent on the menstrual cycle?
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Describe the formation of the zona pellucida. Describe its structure. What is the ZP important for?
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Describe the secondary follicle. Is this dependent on the menstrual cycle?
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Describe the tertiary follicle. Is this dependent on the menstrual cycle? What happens in the tertiary follicle?
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How many dominant follicles are there at one time?
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Sketch the structure of an ovary
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What hormones are involved? Where are each of these secreted? What are their roles?
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What is the name of the axis that describes the hormones interaction with the gonads?
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What are the 2 types of somatic cells in the follicle? What are their roles?
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What is the name of the hypothesis that describes how these cells release their hormones?
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Sketch the cells and the hormones they release and how they interact
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What hormones control the output of these cells? What effect do these hormones have?
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What are the 2 main ovarian hormones?
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What is the role of oestrogens?
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What is the role of progesterone?
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Sketch how hormone levels change across the female menstrual cycle and mark where ovulation occurs
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What days in the cycle is menstruation?
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What days are the preovulatory phase? Periovulatory?
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What occurs in the follicular/proliferative phase? _____ secretes ________. In response _____ secretes ______. Up to ______ follicles are rescued. ______ and ______ cells develop in follicles and produce _______ hormone. This thickens the _______ and thins __________. Oestrogen supresses ______ production by the _____________.
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Granulosa in the dominant follicle express what receptor?
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What causes the LH surge? What releases the LH?
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When is meiosis 1 completed?
When does meiosis 2 begin? And at what stage is it arrested in?
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What changes occur in the oocyte structure at this stage?
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What is the cumulus oophorus?
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What is the stigma? And what happens to it on ovulation?
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What picks up the cumulus-oocyte complex? At what time period does this occur?
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What is the luteal phase? What is a corpus luteum?
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What are theca cells?
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What happens to the endometrium during the luteal phase? What type of feedback occurs here and what hormones does it involve?
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What hormone is produced when pregnant and by what cells? What receptor on what cells does this bind to? What does this hormone do?
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What hormones are produced to support pregnancy?
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What hormones supress ovulation?
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From what stage in pregnancy does the placenta take over these roles?
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What happens in the repro tract if NOT pregnant? What hormone is not produced? What happens to the corpus luteum? What is it then called?
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What happens to progesterone and oestrogen levels?
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What hormone leaves to breakdown of the endometrium
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What is different about the estrous cycle of humans and some primates?
What occurs in other animals?
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Define gonads
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Define gamete?
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Define germ cell?
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What are the precursors to germ cells
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Up until what age are female and male gonad development the same?
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The presence of _______ leads to testes formation
____ _____ ______ = controller gene for testes
formation also known as _____ gene
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What happens to female mice with SRY gene? What gonads do they develop?
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What happens in week 7 of testes development. Columns of cells from _____________ proliferate and penetrate ___________ (deeply or shallowly?)
Sketch and label what this looks like
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What cells form the vasculature? Where do they migrate from?
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What are leydig cells?
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What makes up a testes?
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Where are the prospermatogonia?
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Where is the vasculature and leydig cells?
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When does SRY stop being expressed
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What are sertoli cells? What do they produce?
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What do leydig cells produce? What is the effect of this?
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What are the 2 testis comparments and what are the 2 things produced by post pubertal testis?
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What is the name of the barrier protecting the testis from blood borne chemicals? Where is this? What junctions link ______ cells to eachother?
When does this barrier develop?
What are the 2 functions of this barrier?
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What are the 3 phases of spermatogenesis?
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When are prospermatogonia reactivated? Where do they undergo mitosis?
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What are the spermatogonial stem cells called?
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What are the names of the sperm at each stage of the proliferation process?
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Where does the primary spermatocyte move to? What does this need to pass through?
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sperm - Where does it undergo its first meiotic division? What does this form?
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sperm - What stage is also known as differentiation?
What structural change occurs at differentiation?
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What is the acrosome?
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sperm - What is the function of the flagellum? How does it work?
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sperm - What is the function of mitochondria? How does it work?
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What is the function of the nucleus in sperm? How is this different from normal cell nuclei?
Describe the cytoplasm
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How long does this whole process take in humans?
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What is the name of the gonad-hormonal axis?
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Give an example of a regulatory facto that gonads produce
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What is the type of feedback loop in male? How does this differ from female?
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What hormone is produced from where at puberty? What physical factors is this dependent on?
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What does LH do?
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What does FSH do?
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What produces androgens? What is it converted to and by what? Where does it bind?
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What is the name of the cytokine produced by sertoli cells? What is its effect?
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How long is the path compared to a sperm? How many make the journey?
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Where do the sperm mature?
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What is capacitation and where does this occur?
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What is the path the sperm take?How much of the fluid is reabsorbed?
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How long does sperm passage take?
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What is the role of the epididymis in maturation? What are the sections called? What is the function of each section?
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How does the human cauda compare to other animals? What is the consequence of this?
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What is the roe of the vas deferens?
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What are the components of semen? How many ml?
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What is seminal plasma and where is it produced? What is its role?
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What are the seminal vesicles and what do they produce?
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What is the prostate and what does it produce?
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What is the bulbourethral glad (also known as ?) and what does it produce?
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What happens to the semen when it enters the female tract?
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What are spermatheca?
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How long can sperm survive in the female tract?
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