just everything

Question 1

oct4 k/o in mice and humans

Answer 1

mice: blastocysts still form, but ICM all differentiate to trophectoderm

humans: if gene encoding is deleted (POV5F1?), then iCM + blastocyst formation = compromised

Question 2

NANOG is a key factor in what

Answer 2

epiblast specification

Question 3

CDX oppresses?

Answer 3

OCT4 in the TE

Question 4

Cdx2 k/o

Answer 4

oct4 isn’t downregulated, so the blastocyst forms but then collapses and arrests

Question 5

human embryos treated with FGF/ERK inhibitors

Answer 5

do not form epiblast - only ICM

Question 6

IGF1 is what

Answer 6

a survival factor, it stimulates protein synthesis

Question 7

FGF4 maintains what

Answer 7

trophoblast SC population

Question 8

fertility problems affect how many people uk world

Answer 8

1/6 uk
10% (3.5mil) world

Question 9

female factors to infertility

Answer 9

failure to ovulate
blocked/filled fallopian tubes
endometriosism

Question 10

male factors to infertility

Answer 10

low # sperm
poor sperm motility
suboptimal # of normal sperm

Question 11

ART diagnostics female

Answer 11

of oocytes
morphology of oocytes (immature, mature MII, degenerated)
ability of oocytes to be fertilized

Question 12

ART diagnostics male

Answer 12

sperm # and quality
ability to fertilize egg (ability to penetrate zona pellucida)

Question 13

ART diagnostics embryo quality

Answer 13

cleavage rate (pattern and timing)
blastocyst foration
PGD-aneuploidy, chromosomal abnormalities

Question 14

steps of natural fertilization

Answer 14

1. oocyte at metaphase II released
2. fertilized by single sperm - zygote
3. pre-implantation development in fallopian tube
4. implantation of blastocyst in uterus - pregnancy

(IVF = 1-3 outside body)

Question 15

early vs late embryo transfer pros and cons

Answer 15

early:
- no chance to assess which embryo are likely to be viable /healthy
- being put back in uterus as cleavage stage embryo = wrong environment
- avoids potentially damaging culture conditions

day 5 transfer (later):
- allows morphological assessment of choice of best blastocyst
- culture env. may have adverse conditions / consequences
- if embryos didn’t survive in vitro, no emryos can be transferred

Question 16

decidualization

Answer 16

stromal fibroblasts transform to become enlarged decidual cells - in respnse to progesterone (and to inflammatory signals when implantation = underway)

decidual cells secrete regulatory signals to control immune microenvironment and to provide a permissible environment for gestation

only progesterone is required to signal for decidualization in humans

Question 17

in conception, the implanting embryo produces what to maintain progesterone levels

Answer 17

hcg

Question 18

only ____ produce HCG

Answer 18

trophoblast - must develop rapidly to produce enough HCG to signal

Question 19

hcg does what

Answer 19

rescues corpus luteum (luteotrophic) - it can then continue to produce progesterone

Question 20

histioptrophic nutrition

Answer 20

stroma contributes to producing some nutrients for embryo
nourishes embryo up to 11 weeks via trophoblast, coelemic cavity and yolk sac

Question 21

the steps / stages of placental villous development

Answer 21

primary villous stage (10dpf)
- cytotrophoblast protrusion
secondary villous stage (12dpf)
- extra embryonic mesoderm incursion
- branching - increases surface area
tertiary villous stage (20dpf)
- vascularization

Question 22

core placental functions

Answer 22

1. protective barrier
2. nutrient + gas exchange
3. hormone secretion + production
   - syncytiotrophoblast = placenta’s endocrine tissue

Question 23

mechs of exchange placental

Answer 23

transcellular facilitated diffusion
- facilitated by transmembrane transport proteins
trasnport along [] gradient - maternal plasma glucose [] = higher than fetal
transcellular active diffusion
- mediated by transporter proteins
- requires energy
transcytosis
- receptor mediated - e.g. immunoglobin
- receptor independent - small molecular proteins

Question 24

villous vs extravillous trophoblast functions

Answer 24

villous = transport, immunological barrier, secretion / endocrine
extravillous: anchorage, plugging of arteriolar openings, migration and spiral artery remodelling

Question 25

changes in vasculature in pregnancy

Answer 25

increase in blood by 35-50% - this is accommodated by: - increase in CO, stroke volume, HR - decrease in peripheral resistance

Question 26

chorionic villi does what

Answer 26

imports oxygen from maternal blood regress in the region of the chorioamnion imports oxygen from maternal blood

Question 27

hemochorial placenta requires ___ to flow through intervillous space - it also does what?

Answer 27

maternal blood supplies lipids to fetus in second and third trimester

Question 28

at term, the placenta has a ______ syncytiotrophoblast layer _____ membranes ________ villus diameter

Answer 28

thinner vasculo-syncytial decreased

Question 29

syncytiotrophoblast - layer of ________ cells - terminally ________ - develops by _______ and fusion of ______

Answer 29

multinuclear non-proliferative differentiated proliferation / cytotrophoblast

Question 30

barker hypothesis

Answer 30

correlation between low birth weight and incidence of death from CVD

Question 31

H19 is a negative regulator of what

Answer 31

IGF II

Question 32

IGF II function

Answer 32

promotes placental development and transporter activity

Question 33

liquorice fun fact

Answer 33

has glycyrrhiza = 11betaHSD2 inhibitor consumption is high in scandinavia it can result in earlier labour, cognitive behavioural problems in children (bc high cortisol exposure has effects on brain development) 11betaHSD2 inactviates cortisol by converting it to cortisone

Question 34

FGR does what (4)

Answer 34

reduced cytotrophoblast proliferation increases apoptosis increases synctyal knots placental amino acid transporter activity

Question 35

in humans, GC treatment does what

Answer 35

impairs angiogenesis reduces branching reduces vegfa nd other angiogenic factors reduces IGF-1 expression