Chapter 23 - Teratology

Question 1

Which of the following time intervals best
describes the maximum susceptibility period?

(A) Week 1
(B) Weeks 3–8
(C) Weeks 9–38

Answer 1

B. Week 3 - 8

The embryonic period (weeks 3–8) is the time when the embryo is most susceptible to
teratogens because all organ morphogenesis occurs at this time.

Question 2

Which of the following time intervals best
describes the resistant period?

(A) Week 1
(B) Weeks 3–8
(C) Weeks 9–38

Answer 2

A. Week 1

Week 1 is the resistant period when the conceptus demonstrates the “all-or-none” phenomenon

(i. e., the conceptus will either die as a result of the teratogen or survive
unaffected) .

Question 3

The most common viral infection is

(A) cytomegalovirus
(B) rubella virus
(C) herpes virus type 2
(D) varicella zoster virus
(E) HIV

Answer 3

A. Cytomegalovirus

Cytomegalovirus (CMV) is the most common fetal infection and is the cause of cytomegalic
inclusion disease.

Question 4

Which of the following is a parasite found
in cats?

(A) Treponema pallidum
(B) Toxoplasma gondii
(C) Rubella virus
(D) Cytomegalovirus
(E) Varicella zoster virus

Answer 4

B. Toxoplasma gondii

Toxoplasma gondii is a protozoan parasite found in cats and may be transmitted to the
fetus transplacentally.

Question 5

Warfarin falls into which category of
drugs?

(A) Category X drugs
(B) Category D drugs

Answer 5

A. Category X drugs

Warfarin is a Category X drug.

Question 6

Valium falls into which category of
drugs?

(A) Category X drugs
(B) Category D drugs

Answer 6

B. Category D drug

Valium is a Category D drug.