It is impossible for sperm to be functional (able to fertilize the egg) until after ________.
A) the tail disappears
B) they become spermatids
C) they undergo capacitation
D) they have been stored in the uterus for several days

Answer: C

Estrogen and progesterone maintain the integrity of the uterine lining and prepare the mammary glands to secrete milk. Which of the following structures makes this possible during the first three months of pregnancy?
A) the amnion
B) the chorion
C) corpus luteum
D) corona radiata

Answer: C

The placenta, a vitally important metabolic organ, is made up of a contribution from mother and fetus. Which portion is from the fetus?
A) chorion
B) umbilicus
C) yolk sac
D) amnion

Answer: A

Proteases and acrosin are enzymes. How do they function in reproduction?
A) They neutralize the mucous secretions of the uterine mucosa.
B) They direct the sperm to the egg through chemical messengers.
C) They act to break down the protective barriers around the egg, allowing the sperm to penetrate.
D) Their function is unknown.

Answer: C

The correct sequence of preembryonic structures is ________.
A) zygote, blastocyst, morula
B) zygote, morula, blastocyst
C) blastocyst, morula, zygote
D) morula, zygote, blastocyst

Answer: B

Which of the following is not assessed as part of the Apgar score?
A) heart rate
B) respiration
C) muscle tone
D) temperature

Answer: D

It is impossible for sperm to be functional (able to fertilize the egg) until after ________.
A) the tail disappears
B) they become spermatids
C) they undergo capacitation
D) they have been stored in the uterus for several days

Answer: C

Select the correct statement about fertilization.
A) Both spermatozoa and the ovulated secondary oocyte remain viable for about 72 hours in the female reproductive tract.
B) Millions of sperm cells are destroyed by the vagina's acidic environment.
C) If estrogen is present, the pathway through the cervical opening is blocked from sperm entry.
D) Once inside the uterus, most sperm cells are protected and remain viable.

Answer: B

Which of the choices below occurs if fertilization of the ovum occurs and implantation takes place?
A) The corpus luteum is maintained until the placenta takes over its hormone-producing functions.
B) The corpus luteum degenerates and becomes the corpus albicans.
C) The ovarian cycle begins.
D) Increased levels of FSH will be produced.

Answer: A

Which of the following statements about the events of fertilization is not true?
A) The two pronuclei divide.
B) The head of the sperm forms the male pronucleus.
C) The secondary oocyte completes the second meiotic division.
D) Proteases and acrosin proteinases of the sperm disperse the cells of the corona radiata of the oocyte.

Answer: A

Shortly after implantation ________.
A) maternal blood sinuses bathe the inner cell mass
B) myometrical cells cover and seal off the blastocyst
C) the trophoblast forms two distinct layers
D) the embryo gastrulates (within 3 days)

Answer: C

The trophoblast is mostly responsible for forming the ________.
A) allantois
B) archenteron
C) placental tissue
D) lining of the endometrium

Answer: C

Implantation of the blastocyst is the result of all of the following except ________.
A) phagocytosis by the trophoblast cells
B) proteolytic enzymes produced by the trophoblast cells
C) settling of the blastocyst onto the prepared uterine lining
D) adherence of the trophoblast cells to the endometrium

Answer: A

The formation of endodermal and ectodermal germ layers occurs at ________.
A) fertilization
B) cleavage
C) gastrulation
D) blastula formation

Answer: C

Cleavage as part of embryonic development is distinctive because it involves ________.
A) cell division by mitosis with little or no growth between successive divisions
B) the fusion of gametes
C) splitting the cell into two separate cells
D) meiosis

Answer: A

Which of the following is not a germ layer?
A) ectoderm
B) mesoderm
C) epiderm
D) endoderm

Answer: C

Which of the following is not usually considered a teratogen?
A) aspirin
B) wine
C) thalidomide
D) German measles

Answer: A

Which hormone is not produced by the placenta?
A) human placental lactogen
B) human chorionic thyrotropin
C) relaxin
D) inhibin

Answer: D

Sperm move to the uterine tube through uterine contractions and the energy of their own flagella. What other factor is involved in sperm movement?
A) hormonal attraction to the ova
B) reverse peristalsis of the uterus and uterine tubes
C) the cilia on the apex of the cells lining the endometrium
D) the increased temperature in the vagina, which stimulates sperm motility

Answer: B

Which of the choices below occurs if fertilization of the ovum occurs and implantation takes place?
A) The corpus luteum is maintained until the placenta takes over its hormone-producing functions.
B) The corpus luteum degenerates and becomes the corpus albicans.
C) The ovarian cycle begins.
D) Increased levels of FSH will be produced.

Answer: A