5) By 72 hours after fertilization, the egg has divided into more than 160 cells and is called the morula.

FALSE

6) Implantation begins six to seven days after ovulation.

TRUE

7) A pregnancy test involves antibodies that detect growth hormone (GH) levels in a woman's blood or urine.

FALSE

8) By the end of the embryonic period, at 8 weeks, all the adult organ systems are recognizable.

TRUE

9) Of the three germ layers, the mesoderm forms the most body parts.

TRUE

10) A pregnant woman urinates more often than usual because the uterus compresses the bladder, her metabolic rate and blood volume are increased, and she must also dispose of fetal metabolic wastes.

TRUE

11) The "fluid-filled, hollow ball of cells" stage of development is the blastocyst.

TRUE

12) The embryonic period lasts until the end of the eighth week.

TRUE

13) The embryo is directly enclosed in and protected by the amnion.

TRUE

14) In fetal circulation, one way in which blood bypasses the nonfunctional lungs is by way of the foramen ovale.

TRUE

15) An episiotomy is an incision made to widen the vaginal orifice, aiding fetal expulsion.

TRUE

16) The placenta and its attached fetal membranes are collectively called the afterbirth.

TRUE

17) Human placental lactogen initiates labor.

FALSE

18) Surfactant production in premature infants is rarely a factor in providing normal respiratory activity.

FALSE

19) A blastocyst is a hollow ball of cells, while the morula is a solid ball of cells.

TRUE

20) A zygote is usually formed within the uterus.

FALSE

1) What destroys the zona pellucida sperm-binding receptors? A) the acrosomal reaction B) human placental lactogen C) the process of capacitation D) zonal inhibiting proteins

D

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

D

3) Milk ejection (the letdown reflex) is stimulated by which of the following hormones associated with pregnancy? A) prolactin B) oxytocin C) inhibin D) gonadotropin

B

4) The corpus luteum prevents loss of the implanted embryo through menstruation by secreting ________. A) follicle-stimulating hormone B) luteinizing hormone C) human chorionic gonadotropin D) estrogens and progesterone

D

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

C

6) Relaxin is a hormone produced by the placenta and ovaries. The function of this hormone is to ________. A) ensure the implantation of the blastula B) block the pain of childbirth C) prevent morning sickness D) relax the pubic symphysis

D

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

A

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

A

9) Which hormone maintains the viability of the corpus luteum? A) estrogen B) human chorionic gonadotropin C) progesterone D) human placental lactogen

B

10) Which of the following is NOT a correct matching of a fetal structure with what it becomes at birth? A) foramen ovalefossa ovalis B) ductus venosusligamentum venosum C) ductus arteriosusligamentum teres D) umbilical arteriesmedial umbilical ligaments

C

11) Which body system of a pregnant woman undergoes the most dramatic physiological changes during pregnancy? A) respiratory system B) urinary system C) digestive system D) cardiovascular system

D

12) Thalidomide was once used to treat intense nausea and morning sickness in pregnant women. Unfortunately, if administered at certain points during gestation it resulted in limb malformation. This drug is an example of a(n) ________. A) endocrine disruptor B) carcinogen C) teratogen D) neurotoxin

C

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

C

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

A

15) Prior to the let-down reflex, the mammary glands secrete a yellowish fluid called ________ that has less lactose than milk and almost no fat. A) bilirubin B) colostrum C) meconium D) prolactin

B

16) How long is the secondary oocyte viable and capable of being fertilized after it is ovulated? A) 36-72 hours B) a full week C) 12-24 hours D) 24-36 hours

C

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

D

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

A

19) Gastrulation begins when a groove with raised edges called the ________ appears on the dorsal surface of the embryonic disc. A) notochord B) placenta C) primitive streak D) spinal cord

C

20) Muscle tissue is formed by the ________. A) epiderm B) mesoderm C) ectoderm D) endoderm

B

21) Neural tissue is formed by the ________. A) ectoderm B) endoderm C) mesoderm D) epiderm

A

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

A

23) The cardiovascular system of a newborn must be adjusted after the infant takes its first breath. Which of the following is also true? A) The ductus arteriosus constricts and is converted to the ligamentum arteriosum. B) The urinary system is activated at birth. C) The foramen ovale between the atria of the fetal heart closes at the moment of birth. D) The ductus venosus is disconnected at the severing of the umbilical cord and all visceral blood goes into the vena cava.

A

24) 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) reverse peristalsis of the uterus and uterine tubes B) the cilia on the apex of the cells lining the endometrium C) hormonal attraction to the ova D) the increased temperature in the vagina, which stimulates sperm motility

A

25) At which stage of labor is the "afterbirth" expelled? A) placental B) expulsion C) dystocia D) full dilation

A

26) Which hormone is NOT produced by the placenta? A) oxytocin B) human placental lactogen C) human chorionic gonadotropin D) relaxin

A

27) During which stage of labor is the fetus delivered? A) expulsion stage B) gastrula stage C) placental stage D) dilation stage

A

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

D

29) Which of the following is true in reference to what may pass through the placental barriers? A) hormones, blood cells, and nutrients B) nutrients and respiratory gases only C) respiratory gases, hormones, nutrients, and blood cells D) nutrients, respiratory gases, wastes, and alcohol

D

30) Which of the following is NOT usually considered a teratogen? A) German measles B) nicotine C) aspirin D) wine

C

31) Derivatives of the mesoderm include ________. A) glandular derivatives of the digestive tract B) vertebrae and ribs C) all nervous tissue D) epithelium of the digestive tract

B

32) Derivatives of the endoderm include ________. A) epithelial lining of the respiratory tract B) brain and spinal cord C) heart and blood vessels D) kidneys and gonads

A

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

B

34) Select the correct statement about the special fetal blood vessels. A) The distal parts of the umbilical arteries form the superior vesical arteries. B) The umbilical vein becomes the ligamentum teres. C) The hepatic portal vein forms from the umbilical artery. D) The fossa ovalis becomes the foramen ovale.

B

35) The decidua basalis is ________. A) the tissue that surrounds the uterine cavity face of the implanted embryo B) destined to remain in the uterus after the birth of the infant C) the part of the endometrium that lies beneath the embryo D) not a maternal contribution to the placenta

C

36) At what point is meiosis II completed for the female gamete? A) ovulation B) fertilization C) implantation D) puberty

B

37) A urine test reveals a positive result for human chorionic gonadotropin (hCG). This indicates ________ was successful. A) gastrulation B) fertilization C) ovulation D) implantation

D

38) The first major event in organogenesis is ________. A) myelination B) gastrulation C) ossification D) neurulation

D

39) As pregnancy continues, the increasing bulkiness of the anterior abdomen changes the woman's center of gravity, possibly causing an accentuated lumbar curvature called ________. A) scoliosis B) hunchback C) lordosis D) kyphosis

C

40) As the infant's head is forced against the cervix with each contraction, the cervix effaces, which means that it ________. A) crowns B) dilates C) softens D) thins

D

41) Which of the following refers to the transfer of sperm and harvested oocytes together into the woman's uterine tubes in the hopes that fertilization will take place there? A) in vitro fertilization (IVF) B) zygote intrafallopian transfer (ZIFT) C) rhythm method D) gamete intrafallopian transfer (GIFT)

D

42) In the block to polyspermy, entry of the sperm's contents causes ________ levels in the oocyte's cytoplasm to rise, triggering the cortical reaction. A) calcium ion B) ATP C) phosphate ion D) sodium ion

A

43) Neural tissue develops from the ________. A) endoderm B) mesoderm C) ectoderm D) entoderm

C

44) Cells of the ________ gather around the notochord and neural tube and produce the vertebra and rib at their associated level. A) myotome B) intermediate mesoderm C) dermatome D) sclerotome

D

45) A friend confides that she desires to have children but is having trouble conceiving. Which of the following is true regarding implantation? A) An estimated 60% of implanted embryos later miscarry due to genetic defects of the embryo. B) Detection of human chorionic gonadotropin (hCG) in blood or urine indicates failure of the blastocyst to implant. C) It is estimated that a minimum of two-thirds of all zygotes formed fail to implant by the end of the first week or spontaneously abort. D) In cases where implantation fails to occur, a nonreceptive uterus becomes receptive once again.

C