pre-natal diagnosis and errors in gastrulation

Question 1

The study and treatment of Fetus

Answer 1

Prenatal paediatrics or Fetology.

Question 2

Maternal Serum Screening

Answer 2

Referred to MSAFP plus, measures three other markers in addition to alpha-Fetoprotein

Question 3

Maternal serum alpha-Fetoprotein (AFP)

Answer 3

a protein produced by the fetal liver whose level increases steadily during pregnancy

Question 4

Human chorionic gonadotropin (hCG)

Answer 4

produced by the placenta, with levels peaking at about 14 weeks of gestation and dropping thereafter

Question 5

Unconjugated estriol (uE3),

Answer 5

produced by the placenta

Question 6

Inhibin-A

Answer 6

produced by the fetus and placenta

Question 7

prenatal diagnosis is

Answer 7

routinely done

Question 8

Maternal AFP are high when compared to normal levels at

Answer 8

the same week of gestation in a fetus with Neural tube defects.

Question 9

Maternal hCG and inhibin-A levels are high, and estriol levels are low in

Answer 9

a downs syndrome fetes

Question 10

these test are not for.. but are for

Answer 10

test for diagnosing birth defect, but only indicates the possibility of some types of birth defects. The MSAFP plus screen should always be followed by or combined with other tests because of high false-positive rate.

Question 11

ultrasonography is used to

Answer 11

examine the fetus and could detect a variety of fetal anomalies.

also used for nuchal region translucency screening. Measures the thickness of the clear area at the back of the neck

Question 12

Fetal echocardiography detects

Answer 12

abnormalities of the fetal heart and heart beat

Question 13

Fetuses with Down syndrome and other chromosomal and major heart anomalies accumulate fluid

Answer 13

in the back of the neck during the first trimester of pregnancy.

Question 14

Amniocentesis: Analyses

Answer 14

the amniotic fluid aspirated from the amniotic cavity between 14 – 16 weeks of gestation

Question 15

Chorionic Villus Sampling

Answer 15

Analyses chorionic tissue sample

Question 16

Gastrulation stage in embryonic development – beginning of the third week, is a highly sensitive stage for

Answer 16

teratogenic insult

Question 17

Ingressing epiblastic cells whose fate has already been determined at or before the time of gastrulation may be damaged

Answer 17

by teratogens

Question 18

High doses of alcohol during gastrulation may

Answer 18

kill cells of the anterior midline of the germ disc, leading to deficiency of midline in craniofacial structures and results to an abnormality called Holoprosencephaly.

Question 19

holoprosencephaly

Answer 19

Midline cleft lip
Lack of nasal tissues
Eyes too close together

Question 20

Caudal Dysplasia, also called Caudal Regression Syndrome, Caudal or Sacral Agenesis (e.g. Sirenomelia):

Answer 20

due to mesodermal insufficiency in the caudal-most region of the embryo, which contributes to the formation of the lower limbs, urogenital system and lumbosacral vertebrae.

Question 21

Caudal Dysplasia defects

Answer 21

Hypoplasia and fusion of the lower limbs, vertebral abnormalities, renal agensis, imperforate anus, and abnormalies of the genital organs.

Question 22

Caudal dysplasia or regression syndrome is associated with

Answer 22

maternal diabetes in humans

Question 23

what is sirenomelia

Answer 23

the legs are joined together

error during gastrulation

Question 24

situs inversus

Answer 24

a condition with transposition of the viscera in the thorax and abdomen. - error in gastrulation

Question 25

Laterality sequences

Answer 25

Patients with these conditions do not have complete situs inversus but are predominantly bilaterally either left-sided or right-sided.

Question 26

Those with left-sided bilaterality have

Answer 26

polysplenia.

Question 27

Those with right-sided bilaterality have

Answer 27

asplenia or hypoplastic spleen

Question 28

Patients with laterality sequences are also likely to have other

Answer 28

malformations, especially heart defects

Question 29

Sacrococcygeal teratomas

Answer 29

a condition where remnants of the primitive streak persist in the sacrococcygeal region to form tumours.

Question 30

Sacroccygeal tumour is the most common

Answer 30

gastrulation associated tumour in newborn.

These tumours commonly contain tissues derived from all the three germ layers.