Congentisl Malformatiins And Teratology

Question 0

Congenital malformation , nutrient factors

Answer 0

Folate
Took much or too little zinc
Glucose

Question 1

Genetic factors in congenital malformations

Answer 1

Numerical-> non disjunction of chromosomes-> monosomy, trisomy
Structural-> inversion or translocation, often caused by ration or viruses

Question 2

Teratogenesis

Answer 2

Process whereby an abnormality is induced in a developing organism during uterine life by forgien agents-> teratogens
Must happen during first 3 months

Question 3

Congenital malformations drug factors

Answer 3

Alcohol-> fetal alcohol syndrome-> midline facial abnormalities and effects on behaviour
Antibiotics:
Tetracycline-> effects teeth in third trimester
Anticonvulsants
Anti tumour agents
Thalidomide

Question 4

Congenital malformations, infectious agents

Answer 4

Rubella-> cataracts, cv defects, deafness
Cytomegalovirus-> microcephaly, microphthalmia
Toxoplasma Gondi-> microcephaly, microphthalmia, hydrocephaly
Syphilis-> still birth and miscarriage

Question 5

Congenital malformations, environmental factors

Answer 5

Ionising radiation
X rays
Pesticides, herbicides, fungicides
Pollutants

Question 6

Six principles of teratology

Answer 6

Results is death, malformation, growth retardation or functional disorder
Varies with developmental stage at time of exposure
Act in specific ways
No effect to lethal as dosage increases
Access depends on nature
Susceptibility depends on genotype

Question 7

Embryo toxicity

Answer 7

Direct toxic effect on the cells of the embryo 
Substance many also be toxic to mother
Embryonic cells more sensitive
Either lethal or reduction in growth
 Fairly non specific

Question 8

Changes of teratogenic effect with pregnancy

Answer 8

Up to 9th day completely protected
Pre embryo-> either kills zygote or has no effect as can be completly fixed-> pre differentiation stage
Embryonic stage-> beginning of organogenesis-> most vulnerable
All organ systems functioning by12th week-> low likelyhood of malformation instead functional abnormalities