embryology

Question 1

when does placenta form

Answer 1

beginning of week 2

Question 2

length of pregnancy

Answer 2

40 weeks from last menstrual period- gestation age
38 weeks from conception - fertilization age

Question 3

preterm

Answer 3

child born 3 weeks before due date

Question 4

premature

Answer 4

born before organs are sufficiently developed

Question 5

zygotic period

Answer 5

first 2 weeks

Question 6

oxygenation during zygotic period

Answer 6

diffusion

Question 7

vitelline stage

Answer 7

week 3-8

Question 8

when does the heart begin beating

Answer 8

day 21

Question 9

placental period

Answer 9

week 9-birth

Question 10

when does the skin start to form

Answer 10

week 3

Question 11

how many umbilical arteries and veins

Answer 11

2 arteries and 1 vein

Question 12

neonatal stage

Answer 12

after birth

Question 13

implantation and placenta formation begins when

Answer 13

day 7

Question 14

site of implantation

Answer 14

decidua basalis

Question 15

placenta covering the embryo

Answer 15

decidua capularis

Question 16

placenta lining the inner uterine cavity

Answer 16

decidua parietalis

Question 17

components of placenta

Answer 17

decidua basassi
intervillous space
chorionic plate

Question 18

placental septum

Answer 18

evaginations of decide basalts unto intervillous space

Question 19

cotyledon

Answer 19

decidua basassi between placental septums

Question 20

cells that implant

Answer 20

syncytiotrophoblastic cells

Question 21

what else do the syncytiotrophoblasts do

Answer 21

surround the embryo

Question 22

precursor of the intervillous spave

Answer 22

trophoblastic lacuna

Question 23

maternal capillary combines with trophoblastic lacunae via

Answer 23

anastomosis

Question 24

which cells migrate to myometrium to anastomose

Answer 24

cytotrophoblast

Question 25

2 steps of anastomosis

Answer 25

loss of smooth muscle coat of arteries
cytotrophoblastic cells replace endothelial cells of artery

Question 26

interillous space blood mixing

Answer 26

oxygenated and deoxygenated blood mixes and diffuses through chorionic villi

Question 27

primary stem, secondary and tertiary villus becomes

Answer 27

chorionic villus

Question 28

secondary stem villus quality

Answer 28

extra embryonic mesoderm in villus

Question 29

tertiary stem villus characteristic

Answer 29

vessels present

Question 30

anchoring villi

Answer 30

villi from the fetus to the decidua

Question 31

chorionic villi

Answer 31

villi from the fetus into the intervillous space

Question 32

chorion frondosum

Answer 32

chorionic villi are only present where the decidua basalis is

Question 33

loss of muscle tone in myometrium, vessels not contracted correctly and risk of hemorrhage after delivery

Answer 33

vaginal atony

Question 34

tissue surrounding umbilical vessels

Answer 34

jelly of wharton

Question 35

umbilical vein carries

Answer 35

oxygenated blood

Question 36

umbilical arteries carry

Answer 36

deoxygenated blood

Question 37

placental membrane

Answer 37

4 layered tissue that separates fetal and maternal blood

Question 38

layers of placental membrane out to in

Answer 38

syncytiotrophoblast
cytotrophoblast
connective tissue
fetal endothelium

Question 39

components of the connective tissue of placental membrane

Answer 39

myofibrils
smooth muscle cells
macrophages
fetal APCs

Question 40

late pregnancy layers of placental membrane

Answer 40

syncytiotrophoblast comes in contact with the fetal endothelium

Question 41

at delivery, where does the decidua basalts separate from uterus

Answer 41

spongy zone

Question 42

source of fetal DNA in maternal plasma

Answer 42

degradation of the syncytiotrophoblasts