Answers 100% Verified
Extrinsic factors for abnormal morphogenesis - ANSWER - deformation, disruption, lower
recurrence risk
Intrinsic factors for abnormal morphogenesis - ANSWER - malformation (single, multiple),
dysplasia (single tissue type) higher recurrence risk
major causes of birth defects... - ANSWER - KNOWN (40%) - multifactorial (20%), single gene
(8%), environments agents (6%), chromosome anomalies (6%), UNKNOWN (60%)
leading cause of death in term newborns - ANSWER - congenital anomalies, 1/30 newborns has
a significant birth defect
paternal origin of aneuploidy - ANSWER - 45,X (Turner), 47,XYY
deformation - ANSWER - abnormal mechanical force that alters shape of, but does not destroy,
an otherwise normal organ without halting morphogenesis (twins, abn shaped uterus)
oligohydramnios can cause - ANSWER - facial compression and pulmonary hypoplasia
breech presentation can cause - ANSWER - dislocated hip
entrapment in a bifid uterus can cause - ANSWER - torticollis and craniofacial asummetry
Adams oliver syndrome - ANSWER - malformation autosomal dom with variable expression,
incomplete penetrance, ectrodactyly, symmetric scalp and skin defects, heterozygous mutation,
mistaken for amniotic band seq
malformation - ANSWER - intrinsic factors that result in abnormal tissue or defective
morphogenesis
, isolated neural tube - ANSWER - malformation failed closure of neural tube at 28 days,
mulitfactorial, 3% recurrence, folic acid to prevent!
multiple gestations or large for gestation age babies can cause - ANSWER - intrauterine
constraint
absence of normal mechanical force - - ANSWER - high arched palate in myotonic dystrophy
deformation - Potter sequence - ANSWER - deformation sequence dysplasia - renal agenesis is
initial event causing oligohydramnios sequence which causes the (genu recurvatum, rocker
bottom feet, large flat ears)
deformation - Breech position in utero - ANSWER - deformation facial/cranialasymmetry,
alveolar ridges approximate on right side first, pressure from foot in utero distorted mandible
deformation -micrognathia - ANSWER - facial compression due to transverse lie
deformation -compression and extra-uterine gestation - ANSWER - placenta attached to exterior
uterus, fetus compressed by mothers ab organs, pulmonary hypoplasia from low amniotic fluid,
flat ear and nose, windswept toes
distruption - ANSWER - extrinsic factor that destroys otherwise normal tissue and interrupts
normal morphogenesis (toxins, trauma etc)
disruption - teratogen - ANSWER - teratogens - only preventable birth defect (most drugs are
not major teratogens except alcohol/tobacco)
retinoic acid - ANSWER - disruption - accutane, absence of EAC, ear, aortic arch, brain defects,
SAB
thalidomide - ANSWER - disruption - can treat cancer and autoimmune - limb defects,
phocomelia (hands or feet are attached close to the trunk, the limbs being grossly
underdeveloped or absent)