phys - repro Flashcards
Why is a rise in Ca2+ levels in the oocyte cytoplasm important during fertilisation?
initiates cortical reaction that hardens zona pellucida –> prevent polyspermy
What drug could be used to inhibit premature labour?
a. Oxytocin antagonist
b. Prostaglandin
c. Glucocorticoid
d. Oestrogen agonist
a. oxytocin antagonist
c. cortisol stimulate release of oestrogen –> promote uterine contractions
hormones that initiate labour:
1. oestrogen
- coordinated contractions,
- breakdown collagen fibres of cervix –> cervix becomes soft and flexible
- prostaglandins
- potent stimulator of uterine smooth muscle contractions
- act on cervix to increase compliance - oxytocin
- potent uterine smooth muscle stimulant
what hormone is released by follicle cells during the follicular phase of the ovarian cycle?
oestrogen
what is the main hormone secreted by corpus luteum?
progesterone
what hormones do sertoli cells secrete?
Anti-mullerian hormone
Inhibin
what cells secrete androgen binding protein?
Sertoli cells
what is the function of androgen binding protein?
bind to testosterone in tubular lumen –> allow high concentration of testosterone in lumen –> promote sperm production
During pregnancy, which hormone maintains the viability of the corpus luteum?
a. Human chorionic gonadotropin
b. Progesterone
c. Oestrogen
d. Anti-mullerian hormone
a. human chorionic gonadotropin
negative feedback on sperm production is carried out through which hormone?
a. FSH
b. LH
c. inhibin A
d. inhibin B
d. inhibin B
sperm motility is gained in which part of the testicles?
epididymis
which part of the fallopian tubes does fertilisation usually occur?
ampulla of fallopian tube
if no pregnancy occurs, when does corpus luteum degenerate?
after 10 days
3 months (with pregnancy)
the thickening of endometrium is a result of which hormone?
oestrogen
what are CD9 and izumo proteins for?
for sperm-egg fusion
CD9 (females)
izumo (males)
which component of the blastocyst invades the endometrium to bury the blastocyst?
syncytiotrophoblast layer
which component of the placenta is involved in the exchange of nutrients, waste and electrolytes between the foetus and mother?
chorionic villi
which hormone inhibits uterine contractility?
progesterone
which hormone stimulates growth of uterine muscles and supplies contractile force needed for delivery of foetus?
oestrogen
which of the following is not a maternal adaptation to pregnancy?
a. increased TPR
b. increased GFR
c. decreased gut motility
d. increased ventilation
a. increased TPR
rather, there is decreased TPR to increase blood volume
when does meiosis II of secondary oocyte take place?
when oocyte is fertilised with sperm
how long does it take for oocyte to move from ovary to uterus?
~4 days
how long does a mature sperm take to make?
~10 weeks
how long does folliculogenesis take?
~6 months
the first sign of puberty in girls is:
a. menarche
b. thelarche
c. gonadarche
d. pubarche
b. thelarche
Oxytocin stimulates uterine contractions by:
a) Reducing serum estrogen levels
b) Increasing the concentration of prostaglandins
c) Stimulating myoepithelial cells surrounding alveoli to contract
d) increasing progesterone synthesis
b. increasing concentration of prostaglandins
oxytocin, oestrogen and prostaglandins promote uterine contractions
c. promote milk letdown (lactation)
Which of the following combinations triggers labor?
a) Reduced progesterone, reduced prostaglandins
b) Reduced progesterone, increased prostaglandins
c) Increased progesterone, reduced prostaglandins
d) Increased progesterone, increased prostaglandins
b) Reduced progesterone, increased prostaglandins
During the menstrual phase, the endometrium undergoes which of the following changes?
a. Prostaglandins decrease causing arteriole vasoconstriction
b. Spiral arterioles dilate, resulting in haemorrhage
c. Increased progesterone receptor expression
d. Glands and stroma enlarge and arteries elongate
b. Spiral arterioles dilate, resulting in haemorrhage
a.prostaglandins increased during menstrual phase –> promote uterine contractions
c. proliferative phase
d. secretory phase
what hormonal changes are there during pregnancy?
- increased progesterone and oestrogen to promote uterine growth
- increased human chorionic gonadotropin (hCG) to maintain viability of corpus luteum
which hormone stimulates maternal appetite and increases fat deposition during pregnancy?
progesterone
what is the function of human placental lactogen?
Stimulate maturation of breasts for lactation
what is the function of human chorionic thyrotropin (hCT) during pregnancy?
Increases parathyroid hormone and activated vitamin D levels –> maintain Ca2+ balance throughout pregnancy (foetus have enough Ca2+ to mineralise bones)
what hormones are involved in the initiation of labour?
- oxytocin
- prostaglandins
- oestrogen
what is the effect of high oestrogen and progesterone on milk production?
inhibit milk production
what is the function of myoepithelial cells surrounding breast alveoli?
- Contract to assist in milk ejection reflex (milk letdown)
- Oxytocin bind to receptors on myoepithelial cells
what hormones are involved in breast enlargement to prepare for lactation?
- progesterone
- oestrogen
- human placental lactogen
Time from onset of cycle irregularity through until 12 months after last menstrual period
what is this?
perimenopause
Permanent cessation of menstrual cycles following loss of ovarian follicular activity
what is this?
menopause
Cessation of ovarian function occurring before age of 40 years
premature ovarian insufficiency
list some effects of menopause on the body
- vasomotor symtpoms (hot flushes, night sweats)
- weight gain
- decreased sexual health
- sleep disturbance
- mood (anxiety, depression)
- urogenital changes
- decrease in production of vaginal lubricating fluid
- loss of vaginal elasticity and thickness
- mucosal thinning of bladder and urethra - increased bone loss
- metabolic syndrome
- CVS disease (increased visceral fat)
During the secretory phase of the uterine cycle, the human endometrium:
A. allows implantation of an embryo in the absence of endometrial glands
B. responds to estrogen but not progesterone
C. sheds the functional layer but not the basal layer
D. undergoes glandular enlargement, artery elongation and secretes glycogen
E. undergoes proliferation of the stroma and endometrial glands
D. undergoes glandular enlargement, artery elongation and secretes glycogen
Jill Black is a 12-year-old girl. She has grown 5 centimetres in the past 4 months. She first noticed breast development at the age of 10, and has recently noticed some hair growth over her groin and axillae. Which of the following statements is TRUE regarding Jill?
A. Her anterior pituitary is now actively secreting GnRH in a pulsatile manner.
B. Her growth spurt is related to the presence of androstenedione in the circulation.
C. Her hypothalamus recently began to continuously secrete GnRH.
D. Her serum FSH levels are likely to be low.
E. Her serum LH levels are likely to be low.
B. Her growth spurt is related to the presence of androstenedione in the circulation. (maturation of zona reticularis)
a. hypothalamus secretes GnRH
c. secrete from birth (low duir
d. high FSH
e. high LH
what hormone is responsible for breast alveoli growth?
progesterone
what hormone is responsible for milk duct growth and branching?
oestrogen
