Deck 8: Developmental Disorders: Causes, mechanisms, and Patterns

Question 1

Which of the following anomalies can be attributed to a disturbance in tissue resorption?

A)Pelvic kidney
B)Cleft lip
C)Anal atresia
D)Renal agenesis
E)Intrauterine digital amputation

Answer 1

C

Question 2

Anencephaly is associated with a deficiency of ____________ in the maternal diet.

A)Vitamin A
B)Folic acid
C)Iodine
D)Insulin
E)Cortisone

Answer 2

B

Question 3

What percentage of congenital malformations is due to unknown causes?

A)5%
B)10%
C)25%
D)50%
E)75%

Answer 3

D

Question 4

Phocomelia results from exposure to which human teratogen?

A)Retinoic acid
B)Alcohol
C)Aminopterin
D)Thalidomide
E)X-irradiation

Question 5

Folic acid deficiency is now thought to be a major cause of what class of malformations?

A)Trisomies
B)Neural tube defects
C)Ambiguous genitalia
D)Polyploidy
E)Duplications

Question 6

Amniotic mesoderm is situated most closely to the _______________.

A)Amniotic cavity
B)Embryonic ectoderm
C)Extraembryonic coelom
D)Yolk sac endoderm
E)Cytotrophoblast

Question 7

Which of the following pairs is correctly matched?

A)Unilateral renal agenesis - failure of migration
B)Tracheoesophageal fistula with esophageal atresia - failure of induction
C)Annular pancreas - failure of induction
D)Pelvic kidney - failure of migration
E)Duplication of ureter - failure of resorption

Question 8

Which of the following is responsible for the largest percentage of congenital malformations?

A)Maternal infections
B)Chemical teratogens
C)Genetically based conditions
D)Ionizing radiations
E)Unknown factors

Question 9

What was the earliest recognized cause of human birth defects?

A)Excess vitamin A
B)Rubella
C)Folic acid deficiency
D)Thalidomide
E)X-radiation

Question 10

Phocomelia is most likely to be seen after maternal exposure to which of the following teratogenic agents during the first trimester of pregnancy?

A)Alcohol
B)Aminopterin
C)Androgens
D)Ionizing radiation
E)Thalidomide

Question 11

Administration of supplemental folic acid has markedly reduced the incidence of _______________.

A)Anencephaly
B)Down syndrome
C)Phocomelia
D)Cyclopia
E)Fetal alcohol syndrome