reproductive system Flashcards
how many chromosomes do cells have
22 pairs of autosomes and 1 pair of sex chromosoddfsmes (allosomes)
What is a Barr body
one of the x chromosomes in a woman is inactivated and forms a darkly stained body attached to the nuclear membrane
when do sex differences appear in an embryo and what are those differences.
after 8 weeks, males will develop the wolffian ducts which is driven by the SRY gene from the Y chromosome
females will develop the mullerian ducts (AMH) absent
which structures develop into the sex organs
the gonadal cortex forms the ovaries
the gonadal medulla forms the testes
why does the wolffian duct regress in females
testosterone absent
why does the mullerian duct regress in males
AMH is present. AMH is developed from the SRY gene
what is CAIS
complete androgen insensitivity in a male sex embryo prevents the development of male physical features despite adequate testosterone levels. This results in pseudohermaphrodism.
what is 5 alpha reductase pseudohermaphrodism
5 alpha reductase is the hormone involved in synthesising DHT from testosterone. DHT is responsible for developing the external male genitalia. If there is no enzyme then there can be no external male genitalia.
which enzyme converted androgens to estrogens
aromatase
what gonads will form if SRY gene is absent
ovaries
what are secondary sex characteristic and what hormone influences the development of them
differentiate males from females. other than primary sex characteristics
body shape, muscle mass, voice, hair
androgens
what significant events occur during puberty
pulsatile secretion of gonadotropin releasing hormone (GnRH)
further sexual differentiation.
how does the brain direct reproduction
hypothalamus and anterior pituitary gland work together to secrete releasing hormones which control the release of steroid sex hormones from the gonads.
GnRH –> (FSH, LH) –>steroid sex hormones (testosterone, estrogen, progesterone)
True or False: both sexes produce androgens and estrogens
true
which structures produce sex steroids
gonads and adrenal gland
what does FSH do
gamete production and development
what does LH do.
synthesis and release of steroid and peptide hormones.
and gamete production in females
what type of feedback does low levels of estrogen produce on its trophic hormones
negative
what type of feedback does high levels of estrogen produce.
postive
what hormonal event causes ovulation
LH surge and as a result higher estrogen and progesterone
what does the follicle secrete that prevents more follicles from developing
AMH
what is the corpus luteum and what does it do
it is the remainder of the follicle after ovulation. It secretes inhibin, progesterone, estrogen
what factors can disrupt reproductive function in women
stress
nutrition
changes to day night cycle
melatonin (seasonal breeding hormone)
environmental estrogen exposure
what differences to the female reproductive cycle can an athlete expect
delayed onset of puberty (primary amenorrhea)
variable menstrual cycle
