placental development

Question 1

sperm capacitation (3)

Answer 1

removal of epididymal and seminal glycoproteins

• increase membrane permeability to Ca2+
• Ca2+ influx maximizes cAMP, increaes sperm motility

Question 2

3 main events in fertilization

Answer 2

acrosome reaction
sperm binding ZP3
sperm-egg fusion

Question 3

acrosome rxn and ZP3

Answer 3

sperm binds ZP3 R on ZP while acrosome reaction takes place to break down ZP

Question 4

cortical rxns

Answer 4

after first sperm fertilizes the egg cortical granules present in the egg remove oligosacch on ZP3 and partially cleave ZP2
-sperm cannot bing now

Question 5

what ig superfamily protein on sperm and other protein on egg are required for sperm and egg fusion

Answer 5

Izumo on sperm
CD9 on egg
-mutation in these prevents fusion

Question 6

fast and slow component of cortical rxn

Answer 6

fast: change in PM potential
slow: cortical rxn

Question 7

implantation of the blastocyst steps

Answer 7

• blastocyst hatches from ZP
• apposition, adhesion to endometirum: integins on trophoblasts and endometrial cells
• implantation by penetrating trophoblastic cells

Question 8

decidual reaction

Answer 8

• optimal state of endometrial maturation for implantation
• glycogen stores, very vascular, pinopodes,
• influenced by progesterone

Question 9

what do syncytiotrophoblastic cells have to get through to invade
what may help hold blastocyst in place

Answer 9

• desmosomes

- pinopodes

Question 10

endovascular invasion

Answer 10

SCT invades into wall of spiral arteries and replace SM cells, disable ability of artery to constrict which keeps it open and have max amount of blood

Question 11

spotting or implantation bleeding

Answer 11

bleeding when blastocyst implants

-can be mistaken for a period

Question 12

what provides an immune protective environment for the development of the embryo

Answer 12

decidua

• secretes immunosuppressive substances such as prostaglandins to inhibit NKC at implantation site
• SCT don’t have MHC II so cannot present to CD4+ cells

Question 13

primary villi

Answer 13

when sytotrophoblastic cell proliferate and extend into SCT

Question 14

secondary villi

Answer 14

when XE mesoderm extends into primary villi

Question 15

tertiary villi

Answer 15

when XE mesoderm differentiate into capillary and blood cells

Question 16

decidua basalis

Answer 16

fnct part of maternal contribution of placenta

-portion underlying the implantation site

Question 17

decidua capsularis

Answer 17

portion overlying implanted embryo, seperates it from uterine cavity

Question 18

decidua parietalis

Answer 18

remainder of endometrium

Question 19

chorionic villus structure

Answer 19

chore of mesenchymal CT and fetal blod vessels

Question 20

placental barrier for exchange

Answer 20

1) SCT
2) cytotrophoblast
3) XE mesoderm
4) fetal endothelium

Question 21

different types of placentas

Answer 21

• bilobed
• circumvallate: umbilical cord on one sise
• succenturinate (extra lobe)
• velamentous cord: placental BV barely covered by CT before going to umbilical cord which can form knot

Question 22

placental abruption

Answer 22

premature separation of normally implanted placenta

• hemorrhage into decidua basalis leads to premature placental separation and bleeding
• can impair oxygenation of fetus

Question 23

placenta previa

Answer 23

implantation of placenta over cervical os

Question 24

placenta accreta

Answer 24

trophoblastic invasion into mymetrium

Question 25

placenta increta

Answer 25

trophoblastic invasion through myometrium

Question 26

placenta percerta

Answer 26

trophoblastic invasion through the uterine wall and into extrauterine space

Question 27

uterine atony

Answer 27

uterine contractions that usually constrict spiral arteries are not strong enough so postpartum bleeding occurs

Question 28

predisposing factor of uterine atony and treatment

Answer 28

uterine fibroids and enlargement of uterus

-infusion of oxytocin

Question 29

placental calcification and risk factor

Answer 29

placenta seems to be programmed to calcify

• if pregnancy last past 40 weeks can happen
• smoking is risk factor

Question 30

lithopedion

Answer 30

ectopic pregnancy with fetus to large to reabsorb so body calcifies it

Question 31

gestational trophoblastic disease

Answer 31

benign and malignant neoplasms arising from fetal tissue invading maternal host

• trophoblastic tissue
• elevated B-hCG is marker

Question 32

complete mole (2)

Answer 32

egg w/ no chrom fertilized by 2 sperm or by 1 sperm that duplicates chroms

Question 33

partial mole

Answer 33

fertlization of haploid ovum and duplication of paternal hap chroms
-extra male chroms

Question 34

complete mole fetal tissue

Answer 34

absent

Question 35

complete mole hydropic villi

Answer 35

extensive grapelike clusters

Question 36

complete mole trophoblastic hyperplasia

Answer 36

extensive with significant atypia

Question 37

partial mole fetal tissue

Answer 37

present

Question 38

partial mole hydropic villi

Answer 38

limited and focal

Question 39

partial mole trophoblastic hyperplasia

Answer 39

focal with mild atypia

Question 40

malignant GTDs: invasive mole

Answer 40

invasion into myometrium of villi, covered with layers of prolif trophoblastic cells, b-hCG moderately elevated

Question 41

choriorcarcinoma

Answer 41

admixture of malignant cytotrophoblast and SCT, no villi