Extrinsic and Intrinsic Factors in Abnormal Morphogenesis, Exams of Biology

Download Extrinsic and Intrinsic Factors in Abnormal Morphogenesis and more Exams Biology in PDF only on Docsity! MCBM Biology Exam 3 – Clark Questions with Answers Lattest Update 2024 Assured Success Extrinsic factors for abnormal morphogenesis - Correct Answers deformation, disruption, lower recurrence risk Intrinsic factors for abnormal morphogenesis - Correct Answers malformation (single, multiple), dysplasia (single tissue type) higher recurrence risk major causes of birth defects... - Correct Answers KNOWN (40%) - multifactorial (20%), single gene (8%), environments agents (6%), chromosome anomalies (6%), UNKNOWN (60%) leading cause of death in term newborns - Correct Answers congenital anomalies, 1/30 newborns has a significant birth defect paternal origin of aneuploidy - Correct Answers 45,X (Turner), 47,XYY deformation - Correct Answers abnormal mechanical force that alters shape of, but does not destroy, an otherwise normal organ without halting morphogenesis (twins, ban shaped uterus) olgiohydraminos can cause - Correct Answers facial compression and pulmonary hypoplasia breech presentation can cause - Correct Answers dislocated hip entrapment in a bifid uterus can cause - Correct Answers torticollis and craniofacial asymmetry multiple gestations or large for gestation age babies can cause - Correct Answers intrauterine constraint absence of normal mechanical force - - Correct Answers high arched palate in moronic dystrophy deformation - Potter sequence - Correct Answers deformation sequence dysplasia - renal agenesis is initial event causing olgiohydraminos sequence which causes the (genu recurvate, rocker bottom feet, large flat ears) deformation - Breech position in utero - Correct Answers deformation facial/cranial asymmetry, alveolar ridges approximate on right side first, pressure from foot in utero distorted mandible deformation -micrognathia - Correct Answers facial compression due to transverse lie deformation -compression and extra-uterine gestation - Correct Answers placenta attached to exterior uterus, fetus compressed by mothers abs organs, pulmonary hypoplasia from low amniotic fluid, flat ear and nose, windswept toes disruption - Correct Answers extrinsic factor that destroys otherwise normal tissue and interrupts normal morphogenesis (toxins, trauma etc) disruption - teratogen - Correct Answers teratogens - only preventable birth defect (most drugs are not major teratogens except alcohol/tobacco) retinoic acid - Correct Answers disruption - Accutane, absence of EAC, ear, aortic arch, brain defects, SAB thalidomide - Correct Answers 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) tobacco - Correct Answers disruption - growth retardation, miscarriage (about 10% of SABs) alcohol - Correct Answers fetal alcohol spectrum disorder, about 1% of US population, poor growth, microcephaly, irritable babies, ave IQ 65, ADHD, short palpebral fissures, smooth phylum, thin upper lip, small distal phalanges, railroad track ears, heart defect, cleft lip skeletal dysplasia: achondroplasia - Correct Answers most common bone dysplasia, advanced age paternal origin, auto doom, FGFR3 mutt, large head, trident hand, hyper extensible joints skeletal dysplasia: thanatophoric dysplasia - Correct Answers most common lethal bone dysplasia association - Correct Answers pattern of anomalies that occur together more often than expected by chance alone, but not in any single pattern and not necessarily with a single cause VATER association - Correct Answers VSD/vertebral, Anus imperforate, Trachea-Esophageal fistula, Radial/Renal defect sequence - Correct Answers pattern of anomalies in which primary defect leads to one or more secondary defects, cascade effect holoprosencephaly sequence *** - Correct Answers HPE, common 1/10k, 1/250 SABs, failure of cleavage of cranial hemispheres: lobar/semi lobar/lobar, premaxillary agenesis, midline defect in brain often, maternal DM association ("face predicts brain"), no midline frenulum, single central incisor, sonic hedgehog SHH gene deletion MLPA - Correct Answers multiple ligation dependent probe amplification detects DELETIONS - sanger sequencing - Correct Answers -DNA set based on premature chain termination -adds small dideoxynucleotides to cut into fragments, sort on gel electrophoresis, four separate expel, run once for each base, computer stuff -limitations - large deletions/duplications (1+ exons), mutations that eliminate splice sites, mosaics, gene rearrangements/position effects, mutt/del up or downstream from promoter NGS (next gen sequencing) - Correct Answers high throughput parallel sequencing of fixed DNA clusters, four fluorescent labels sanger vs next gen set - Correct Answers NGS is faster genetic tests: specific uses and limitations - Correct Answers