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