Placenta Info + Related problems in medicine

Question 1

Wharton’s jelly

Answer 1

a placental cord gelatinous connective tissue: it is seen at partuition when it increases in volume to assist closure of placental blood vessels: matrix from jelly identified as potential stem cells

Question 2

Umbilical cord blood stem cells have contributed treating ____ number of diseases since 1988

Answer 2

121

Question 3

Umbilical Vein or Veins?

Answer 3

There are 2 during development: the right one deteriorates under normal circumstance @ second month of development: LEFT umbilical vein persists/devliering blood from placenta to the developing fetus

Question 4

Persistent right umbilical vein

Answer 4

Uncommon vascular anomaly; present in 2/1000 births

normall the right umbilical vein begins to obliterate in the 4th week of gestation and disappears by the 7th week

Question 5

Morphology of Placenta+with umbilical cord: which one should disturb us?

Answer 5

These are fine: Bilobed/Circumvallate/Succenturinate

VELAMENTOUS CORD

Question 6

Velamentous cord

Answer 6

fetal blood vessels travel abnormally

pass through amniochorionic membrane before reaching the placenta

vessels are more exposed to trauma during the birth process

Question 7

Abnormalities of Placental Implantation (2, with sub-distinctions)

Answer 7

Placenta previa: implantation of the placenta over the cervical os (opening)

Placenta accreta (abnormal trophoblastic invasion into the

1) muscular layer of the uterus (placenta increta)
2) surrounding tissue (placenta percerta)

Question 8

Placental accreta/increta/percreta

Answer 8

When trophoblast grows past uterine wall into

1) Trophoblast grows too deep into the uterine muscle
1) Trophoblast grows through the uterine muscle (placenta increta)
2) Trophoblast grows beyond uterus into organs (placenta percerta)

Question 9

Placenta Previa

Answer 9

1) Low hanging: near but does not cover cervix os
2) Partial covering of cervix OS
3) Total Covering

Question 10

Placental Endorcrine Functions:

Answer 10

Synthesizes a) cholesterol b) fatty acids c) hormones d) glycogen

Hormones: hCG, progesterone (maintains endometrium), estrogen (estrodiol), human placental lactogen (hPL), induces lipolysis, elevating free fatty acids in mother
“growth hormone” of fetus

Question 11

hPL

Answer 11

human placental lactogen (hPL): induces lipolysis, elevating free fatty acids in mother

growth hormone of the fetus

Question 12

Placental calcification

Answer 12

theories include old age, reduced blood supply, smoking

pattern of calcification is seen in other aging tissues

Question 13

Lithopedion

Answer 13

ectopic pregnancy termination in which body of dead fetus calcifies

Question 14

Amniotic Fluid

Answer 14

permits symmetrical external growth

enables fetus to move frely

acts as a barrier to infection

permits normal fetal lung development

prevents adherence of aminion to embryo/fetus

helps maintain homeostasis (temp, fluids, electrolytes)

Question 15

Oligohydraminos

Answer 15

Low volume of amniotic fluid

associated with renal agenesis+obstructive uropathy

complications: pulmonary hypoplasia and limb defects

Question 16

Consequences of Oligohydraminos related renal agenesis

Answer 16

Potter syndrome

for normal development amniotic fluid must be brought into the lung by fetal breathing movements, leading to distension of the developing lung

Question 17

polyhdramnios

Answer 17

high volume of amniotic fluid

associated with CNS anomalies and esophageal atresia

Question 18

Amniotic band syndrome

Answer 18

tears in the amnion detach and surround fetus

or adhesions between the amnion and affected structures

may cause ring constriction or amputations of limps or digits

Question 19

Development of blood vessels (2 ways)

Answer 19

1. Vasculogenesis: blood vessels arise from coalescence of hemangioblasts, which arise from blood islands
2. angioblasts- vessel formation via branches arising from existing vessels, major form via vasculogenesis

Question 20

Major blood vessels form during _____

Answer 20

vasculogenesis

Question 21

Vasculogenesis begins in

Answer 21

splanchnic layer covering yolk sack

Question 22

Definitive hematopoietic stem cells (AGM)

Answer 22

formation of blood cells in the yolk sac transitory, definitive hematipoietic cells arise from mesoderm around the aorta

aorta-gonad-meonephros region (AGM)

the cells will colonize the liver

Question 23

Hematopoietic tissue in the fetus

Answer 23

stem cells colonize the liver- major hematopoietic organ of the fetus

later stem cells from the liver colonize the spleen, thymus and ultimately the bone marrow

Question 24

Path of hematopoietic cells —>

Answer 24

Aorta-gonad-mesonephros region (AGM)—> colonize the liver (major hematopoietic organ of the fetus)