If neither testosterone nor mullerian-inhibiting hormone is secreted during embryonic development
A. the paramesonephric duct system degenerates.
B. the mesonephric duct system is stimulated.
C. internally female reproductive structures form.
D. the individual appears as a male.
E. internally male reproductive structures form.
(
Question 2) In males, the urogenital folds close over the urogenital opening and urethral groove to form the
A. scrotum.
B. testes.
C. vas deferens.
D. penis.
E. prostate gland.
(
Question 3) The male and female reproductive systems begin as an indifferent stage. If testosterone is present, which of the following occurs?
A. The paramesonephric duct forms the vagina.
B. The mesonephric ducts form the ductus deferens.
C. The mesonephric ducts atrophy.
D. The paramesonephric ducts enlarge to form the scrotum.
E. The paramesonephric duct atrophies.
(
Question 4) In females, the genital tubercle becomes the
A. uterus.
B. ovary.
C. clitoris.
D. vagina.
E. labia.
(
Question 5) Cryptorchidism
A. is the failure of the testes to descend into the scrotal sac.
B. may be due to excessive amounts of testosterone in the fetus.
C. has no effect on fertility.
D. results in feminization of the male fetus.
E. is the lack of testes.
(
Question 6) The lungs develop from
A. somitomeres.
B. neural crest cells.
C. an evagination from the foregut.
D. an evagination from the floor of the diencephalon.
E. an invagination from the hindgut.
(
Question 7) The adult kidney develops from the
A. pronephros.
B. metanephros.
C. mesonephros.
D. allantois.
E. neonephros.
(
Question 8) The common junction of the digestive, urinary, and genital systems is the
A. cloaca.
B. coelom.
C. allantois.
D. hindgut.
E. anus.
(
Question 9) The first functional kidney is the
A. mesonephros.
B. pronephros.
C. allantois.
D. bulbos cordis.
E. urorectal septum.
(
Question 10) Which of the following statements concerning the embryonic circulatory system is true?
A. The heart develops from four endothelial tubes.
B. Blood vessels form from blood islands.
C. An opening in the interatrial septum is called the sinus venosus.
D. The bulbus cordis becomes the sinoatrial node (the adult pacemaker).
E. There is an opening in the interventricular septum.