Reproductive Physiology Flashcards
where in the testis is sperm produced?
seminiferous tubules
where is testosterone produced in the testis?
Leydig cells
where is sperm stored before ejaculation?
epididymis
what does sperm pass through before it mixes with fluid from the seminal vesicles?
vas deferens (contractile tube)
fluid then leaves duct and into the urethra to mix with prostate secretions
what stimulates testosterone production?
LH (on Leydig Cell)
where is inhibin produced in males?
Sertoli cells
what stimulates inhibin production?
FSH
what production does LH stimulate in males?
testosterone production in Leydig cells
what production does FSH stimulate in males?
inhibin production in Sertoli cells
what will testosterone bind to and what effect will the complex have?
Testosterone binds to androgen binding protein (ABP) which will stimulate:
- spermatogenesis (in the seminiferous tubules)
- sperm maturation (in the epididymis)
by concentrating the testosterone and making it less lipophilic (so it does not leave)
FSH does this too
state the stages of spermatogenesis and what happens in them (product)
- Germ cells
- 44+XY (diploid).
- Mitotic division - Primary spermatocyte
- 44+XY (diploid).
- 1st meiotic division. - Secondary spermatocyte - 22+X, 22+Y (haploid).
- 2nd meiotic division. - Spermatids - 22+X, 22+Y (haploid).
- Spermatozoa - 22+X, 22+Y (haploid).
when is the haploid created in spermatogenesis?
after the first meiotic division
how much sperm is created a day and when does this process begin in a boy?
100-200 million a day
starts at puberty
what does the ovary mainly produce?
gametes (ovum)
steroids (oestrogens and progesterone)
what is the role of the Fallopian tubes (oviducts) ?
sustain oocyte/conceptus
where does the implantation of the conceptus occur?
in the uterus
what are the main steroid producing cells of the ovarian follicle and which steroids are produced by them?
thecal–> androstenedione (oestrodiol precursor)
granulosa–> aromatase enzyme–< uses androstenedione–> oestradiol
produce progesterone in the second half of MC
what cells in the ovarian follicle produce oestrogen precursors? what stimulates this?
Thecal cells
stimulation by LH
what cells in the ovarian follicle eventually produce oestradiol and progesterone?
granulosa cells
stimulation by FSH
what is the role of progestogens?
maintain endometrium
what is the role of oestrogens?
stimulate the proliferation of the endometrium
what are the cycles that make up the menstrual cycle?
endometrial and ovarian cycle
what are the processes that occur in the endometrial cycle?
phases:
- menstruation
- repair and proliferation
- secretory
what are the processes that occur in the ovarian cycle?
- follicular phase
- ovulatory phase
- luteal phase
what stage does FSH and LH stimulate? what is the product of this stage and what will it lead to?
FSH and LH stimulate the follicular phase (growth of ovarian follicle)
this leads to oestradiol production by the aromatase enzymes released by granulosa cells
this will lead to proliferation of the endometrium (increase in thickness, more glands and arteries etc)
what is the effect of producing oestradiol (E2) in the thickening process of endometrium?
E2 production speeds up as follicles grow and will switch to positive feedback from -ve FB
ovulation will occur
what does the corpus luteum produce?
corpus luteam is the “dead body” left behind after the release of the ovum progesterone and E2
(luteal phase)