Chapter 43
Student: _________________________________________________________
1. All but which of these animals are likely to undergo parthenogenesis?
A. humans
B. flatworms
C. fish
D. lizards
2. Semen contains alkaline secretions for what purpose?
A. Sperm swim better under basic conditions.
B. The female vagina is acidic and thus not a good environment for sperm.
C. Sperm are only able to use fructose under alkaline conditions.
D. The pH of semen has no significance.
3. The release of LH is triggered by what event?
A. a decrease in progesterone levels
B. a decrease in estrogen levels
C. an increase in progesterone levels
D. an increase in estrogen levels
4. Which of the following statements is NOT true about asexual reproduction?
A. It occurs with only one parent.
B. It is less commonly used by vertebrates.
C. It can occur by budding or by division and regeneration.
D. A large number of offspring can be produced in this way in a short time.
E. It produces variation that allows the species to adapt quickly to changing environmental conditions.
5. The Greek root words for "virgin" and "producing" is the basis for the term
A. ovary.
B. conception.
C. copulation.
D. parthenogenesis.
E. ejaculation.
6. What is parthenogenesis?
A. a sexual means of internal fertilization
B. an asexual means of reproduction involving budding
C. an asexual means of reproduction by splitting or fission into several new individuals
D. an asexual means of reproduction by which unfertilized eggs develop into mature individuals
E. a sexual means of reproduction by which cross-fertilization occurs between hermaphrodites
7. The Greek root word for "seed" is the basis for the term
A. sperm.
B. conception.
C. testes.
D. fertilization.
E. gonad.
8. In a species of desert lizard, only females are known to exist. It is necessary for two females to court and for
one to assume the posture of a male to stimulate the other female to ovulate. Of course, no fertilization can
occur. This is a case of
A. hermaphroditism.
B. parthenogenesis.
C. sexual reproduction because the mating behavior is required.
D. a need for further research since only primitive animals can reproduce asexually.
9. The Latin root word for "join" is the basis for the term
A. androgen.
B. conception.
C. copulation.
D. fertilization.
E. ejaculation.
10. What is the probable biological and evolutionary function for a species of desert lizards to return to femaleonly reproduction?
A. This species is probably going extinct.
B. This is not at all unusual since most reptiles are asexual.
C. The desert is uniform, and variation is of little or no advantage and a waste in energy.
D. Such a switch in mating behavior is easily understood as a crossing-over in chromosomes.
11. Which of the following statements is NOT true about reproduction?
A. Gametes are produced by meiosis and may be specialized as eggs or sperm.
B. Hydras may reproduce asexually by budding new individuals from the parent.
C. Asexual reproduction is most advantageous when the environment is continually changing.
D. A hermaphrodite produces both male and female gametes in different specialized gonads.
E. A starfish can be cut into several pieces, and each piece will regenerate all the other parts of the individual.
12. Which of the following statements is NOT true about fertilization?
A. Amphibians, birds, and reptiles lay shelled eggs.
B. Most terrestrial animals practice internal fertilization.
C. Many terrestrial males have a copulatory organ for sperm transfer.
D. Internal fertilization is required for the production of shelled eggs.
E. Most aquatic animals practice external fertilization, releasing gametes into the water.
13. Reptile and bird eggs have
A. no chorion.
B. no amnion.
C. no extraembryonic membranes since the young are inside an egg.
D. a placental connection since these are advanced animals.
E. a plentiful and large yolk since it must support all early development.
14. A placental mammal would be
A. larviparous.
B. viviparous.
C. nefarious.
D. oviparous.
E. ovoviviparous.
15. The male reproductive system includes all EXCEPT which of the following?
A. testes
B. epididymis
C. penis
D. prostate
E. fimbriae
16. Sperm mature within the
A. seminal vesicles.
B. vas deferens.
C. interstitial cells.
D. ejaculatory duct.
E. epididymis.
17. The time interval following ejaculation during which stimulation does not cause erection is called
A. orgasm.
B. impotency.
C. secretory phase.
D. spermatogenic period.
E. refractory period.
18. In the human male, the tube used to carry both sperm and urine is the
A. ureter.
B. seminiferous tubule.
C. vas deferens.
D. urethra.
E. fallopian tube.
19. A functional advantage of having human testes in the scrotum rather than in the abdomen is
A. lack of room in the abdomen.
B. a shorter sperm duct.
C. more direct blood supply.
D. lower temperature.
E. greater protection to the testes.
20. If we cut a cross-section through the testes, we would see
A. individual sperm follicles with all future immature sperm present.
B. large chambers lined with developing sperm.
C. small tubules lined with developing sperm.
D. flat layers of tissue like pages, lined with developing sperm
21. Ultimate control of testes development is by the _____ which secretes _____.
A. anterior pituitary, GnRH
B. anterior pituitary, testosterone
C. anterior pituitary, ICSH
D. hypothalamus, GnRH
E. hypothalamus, testosterone
22. Semen production does NOT involve the
A. testes.
B. prostate gland.
C. seminal vesicles.
D. bulbourethral gland.
E. Graafian follicle.
23. Trace the correct path of the sperm during ejaculation.
A. urethra, vas deferens, seminal vesicles, testes
B. testes, urethra, vas deferens, penis
C. seminiferous tubules, epididymis, vas deferens, urethra
D. seminiferous tubules, vas deferens, epididymis, urethra
E. vas deferens, seminiferous tubules, epididymis, urethra
24. In the human male, sperm cells are produced in the
A. interstitial tissue.
B. urethra.
C. seminiferous tubules.
D. vas deferens.
E. seminal vesicles.
25. Which association concerning structures in the human male is incorrect?
A. testes–produce sperm
B. vas deferens–carries urine
C. prostate gland–seminal fluid
D. urethra–conducts sperm
26. Why do testes shrink when male athletes take synthetic steroid testosterone hormones?
A. Testosterone itself has the direct effect of shrinking the testes.
B. Synthetic chemicals are not the same in action as natural chemicals.
C. The guilt reaction in the brain causes a reverse hormonal action.
D. The pituitary detects high levels of testosterone in the bloodstream and reduces FSH and LH.
E. Scientists have no explanation for this phenomenon that is opposite of expected.
27. Inhibin is a hormone that
A. decreases sexual urges.
B. decreases sperm production in the testes.
C. serves in a feedback to the anterior pituitary to regulate testosterone levels.
D. trigger ovulation in females.
E. prevents or inhibits erection.
28. A male accessory organ that often becomes enlarged, infected, or cancerous in older men is the
A. testis.
B. prostate gland.
C. epididymis.
D. bulbourethral gland.
E. vas deferens.
29. The Latin root word for "seed" is the basis for the term
A. sperm.
B. conception.
C. semen.
D. fertilization.
E. ejaculation.
30. What purpose is served by the presence of the testes in the scrotum rather than in the abdomen?
A. The testes are cooled to the proper temperature for sperm development.
B. The testes are warmed to the proper temperature for sperm development.
C. The testes are exposed to a higher oxygen content in the scrotum for sperm development.
D. The testes are exposed to a lower oxygen content in the scrotum for sperm development.
31. The substances found in semen are produced by all EXCEPT which of the following?
A. prostate
B. vas deferens
C. bulbourethral glands
D. seminal vesicles
E. testes
32. Which part of the sperm cell is lined with mitochondria and expends the energy needed to propel the sperm?
A. acrosome
B. head
C. tail
D. middle piece
33. What is the last part of the male reproductive tract through which the semen passes?
A. vas deferens
B. urethra
C. epididymis
D. prostate
34. What is the function of the sertoli (sustentacular) cells in the male reproductive tract?
A. produce the sperm cells through meiosis
B. produce an alkaline fluid added to the semen
C. activate the sperm cells so they can swim rapidly
D. support and regulate the cells that produce sperm cells
E. produce a fluid added to the semen just before ejaculation
35. In most male animals, the penis or other copulatory organ achieves erection by
A. muscle contraction.
B. testicular pressure.
C. bones or exoskeleton interlocking.
D. artery dilation or hemolymph pressure.
36. What is the main sex hormone of the human male?
A. testosterone
B. estrogen
C. luteinizing hormone (LH)
D. follicle-stimulating hormone (FSH)
E. interstitial cell-stimulating hormone (ICSH)
37. Which structure of the male reproductive tract is often enlarged in older men?
A. vas deferens
B. testis
C. prostate
D. epididymis
E. seminal vesicle
38. Approximately how many sperm are produced each day in a healthy adult male?
A. fifty to seventy thousand
B. several hundred thousand
C. one or two million
D. several hundred million
E. one billion
39. LH is an abbreviation for luteinizing hormone which was described as a female hormone controlling the
ovary. In the male, LH
A. does not exist since males lack ovaries.
B. exists in rudimentary levels since LH is made by the anterior pituitary.
C. is exactly the opposite chemical from male hormones, in an antibody-antigen fashion.
D. controls production of testosterone.
40. Secondary sexual characteristics in the male are directly maintained by the hormone
A. testosterone.
B. estrogen.
C. FSH.
D. TSH.
E. progesterone.
41. LH stimulates the ___ of the testis to produce ___.
A. seminiferous tubules, sperm
B. seminiferous tubules, testosterone
C. interstitial cells, sperm
D. interstitial cells, testosterone
E. interstitial cells, estrogen
42. Which part of the sperm contains energy-producing mitochondria?
A. head
B. middle piece
C. tail
D. acrosome
E. zona pellucida
43. The energy source for sperm to swim comes from
A. stored fat molecules in the acrosome.
B. stored sugar molecules in the sperm head.
C. fructose sugar in the surrounding seminal fluids added by the seminal vesicles.
D. protein breakdown by mitochondria in the mid-piece of the sperm.
E. dissolved lipids in the seminal fluids added by the prostate gland.
44. The role of the acrosome during the fertilization process is to
A. contain enzymes that help a sperm head digest its way into an egg.
B. increase the sperm's motility.
C. direct the sperm to the egg.
D. transport the chromosomes into the egg.
E. store energy for swimming to the egg.
45. The order of the structures in the vulva, from the frontal mons pubis to the anus, is
A. glans clitoris–vagina–urethra.
B. glans clitoris–urethra–vagina.
C. urethra–glans clitoris–vagina.
D. vagina–urethra–clitoris.
E. vagina–glans clitoris–urethra.
46. The egg is propelled down the oviduct by
A. cilia on the layer of nurse cells surrounding the egg.
B. simply drifting on the prevailing current of body fluids.
C. oviduct cilia and tubular muscle contractions.
D. suction from the uterine contractions.
47. Which one of these is NOT part of the human female external genitalia?
A. mons pubis
B. clitoris
C. labia minora
D. labia majora
E. uterus
48. The Latin root word for "womb" is the basis for the term
A. penis.
B. vagina.
C. cervix.
D. uterus.
E. endometrium.
49. The clitoris in the female is homologous to the ____ in the male.
A. testes
B. vas deferens
C. penis
D. scrotum
E. prostate gland
50. The Latin root word for "sheath" is the basis for the term
A. penis.
B. vagina.
C. cervix.
D. uterus.
E. endometrium.
51. Fertilization in humans normally occurs in the
A. uterus.
B. vagina.
C. abdominal cavity.
D. ovarian follicle.
E. oviducts.
52. The Greek root words for "within the womb" is the basis for the term
A. placenta.
B. vagina.
C. cervix.
D. uterus.
E. endometrium.
53. Which of the following statements is incorrect?
A. The follicles in the ovary produce estrogen.
B. The corpus luteum produces progesterone.
C. The placenta can produce both estrogen and progesterone.
D. LH stimulates the formation of the corpus luteum.
E. A surge of FSH is believed to promote ovulation.
54. The structure from which an egg is released during ovulation is called a/an
A. ovarian cyst.
B. primary follicle.
C. corpus luteum.
D. secondary follicle.
E. Graafian follicle.
55. The Latin root word for "yellow body" is the basis for the term
A. placenta.
B. vagina.
C. corpus luteum.
D. uterus.
E. endometrium.
56. LH stimulates the
A. seminiferous tubules of the testis.
B. pituitary to produce ACTH.
C. follicle to produce estrogen.
D. corpus luteum to produce progesterone.
E. interstitial cells to produce inhibin.
57. Normal human sperm and eggs are similar in which one of the following respects?
A. They have the same number of chromosomes in their nucleus.
B. Their locomotion is achieved with equal facility.
C. They have the same relative amount of cytoplasm surrounding their nuclei.
D. Approximately the same number of gametes are produced from both gonads.
E. Both use meiosis to produce four sperm or four eggs from the parent cell.
58. What is the main sex hormone of the female?
A. testosterone
B. estrogen
C. luteinizing hormone (LH)
D. follicle-stimulating hormone (FSH)
E. interstitial cell-stimulating hormone (ICSH)
59. At ovulation, an egg is released from a/an
A. ovarian cyst.
B. primary follicle.
C. corpus luteum.
D. secondary follicle.
E. Graafian follicle.
60. The luteal phase of the ovarian cycle occurs, in a 28-day cycle, at about
A. days 1-5.
B. days 6-13.
C. day 14.
D. days 15-28.
61. Which of the following hormones is best associated with maturation of the egg?
A. follicle stimulating hormone
B. luteinizing hormone
C. testosterone
D. human chorionic gonadotropic hormone
E. progesterone
62. Which of these descriptions could be associated with the luteal phase of the uterine cycle?
A. low FSH, high estrogen, developing follicle, increase in uterine lining
B. high LH, high estrogen, developing follicle, uterine lining breakdown
C. decrease in LH, increase in progesterone, corpus luteum present, secretory uterine lining
D. decrease in LH, decrease in progesterone, corpus luteum present, secretory uterine lining
E. increase in LH, increase in progesterone, corpus luteum present, endometrium released
63. In the human female, the uterine cycle is on the average
A. 20 days.
B. 24 days.
C. 28 days.
D. 32 days.
E. 36 days.
64. During a 28-day uterine cycle, ovulation usually occurs on the
A. 5th day.
B. 9th day.
C. 14th day.
D. 20th day.
E. 25th day.
65. After ovulation, the ruptured follicle
A. disappears and all of its cells disintegrate.
B. passes on as waste material down the oviduct with the egg.
C. mends itself and begins the maturation of another egg.
D. becomes a part of the epithelial covering of the ovary.
E. differentiates into the corpus luteum.
66. Menstruation begins because
A. the pituitary triggers it.
B. LH activity is at its peak.
C. estrogen activity is at a peak.
D. progesterone production is highest.
E. progesterone and estrogen levels are both declining.
67. In the human female, estrogen and progesterone exert feedback control over the
A. pituitary.
B. ovary.
C. uterus.
D. testes.
E. prostate gland.
68. The uterine cycle at day 12 would primarily be under the influence of
A. estrogen.
B. progesterone.
C. epinephrine.
D. thyroxin.
E. testosterone.
69. Which structure in humans produces FSH?
A. hypothalamus
B. ovary
C. uterus
D. pituitary
E. interstitial cells
70. When an egg erupts from a follicle, the chamber that remains and secretes hormones is the
A. oocyte.
B. stroma.
C. corpus luteum.
D. primary follicle.
E. corpus cavernosum.
71. The lining of the uterus that is discharged during the menstrual phase is the
A. endocardium.
B. oviduct.
C. endometrium.
D. hymen.
E. myocardium.
72. Days 6-13 of a 28-day uterine cycle is called the
A. menstrual period.
B. proliferative phase.
C. ovulation period.
D. secretory phase.
E. fertilization period.
73. In a human female, the secretory phase is part of the
A. ovarian cycle.
B. uterine cycle.
C. sexual cycle.
D. pituitary cycle.
E. testicular cycle.
74. Which of the following is NOT true about estrogen?
A. Estrogen causes the endometrium to thicken.
B. Estrogen causes the endometrium to become vascular and glandular.
C. Estrogen causes a positive feedback on the hypothalamus to secrete GnRH.
D. Estrogen causes a negative feedback on the anterior pituitary gland.
E. Estrogen stimulates the release of FSH.
75. In the human female, fertilization occurs in the
A. uterus.
B. oviduct.
C. vagina.
D. ovary.
E. abdominal cavity.
76. Pregnancy occurs when
A. the sperm and the egg combine.
B. the fertilized egg implants in the ovary.
C. the developing embryo embeds itself in the endometrial lining.
D. sperm are in the vagina.
E. sperm are in the uterus.
77. The hormone produced by cells around the embryo that maintains the corpus luteum and the pregnancy is
called
A. estrogen.
B. progesterone.
C. luteinizing hormone (LH).
D. follicle-stimulating hormone (FSH).
E. human chorionic gonadotropin (HCG).
78. Some animals give birth to a litter of a dozen or so young. Without further information, what would be a
biologically reasonable speculation for the origin of so many embryos?
A. The uterus is designed differently.
B. Not as many embryos are spontaneously aborted.
C. More eggs are triggered to develop than in humans.
D. There is a tendency to have identical twins from division of the fertilized egg.
79. Menstruation begins because
A. the pituitary triggers it.
B. LH activity is at its peak.
C. estrogen activity is at a peak.
D. progesterone production is highest.
E. progesterone and estrogen levels are both declining.
80. The organ that exchanges molecules between fetal and maternal blood is the
A. vagina.
B. oviduct.
C. uterus.
D. placenta.
E. mammary gland.
81. Which statement is wrong regarding HCG?
A. HCG is produced by the placenta.
B. HCG stimulates the anterior pituitary gland.
C. HCG stimulates the corpus luteum.
D. HCG helps maintain estrogen and progesterone levels in the blood.
E. HCG is used in pregnancy testing.
82. Trace the path of the sperm through the female reproductive tract.
A. vagina —> uterus —> oviduct —> cervix
B. urethra —> vagina —> oviduct —> cervix
C. vagina —> cervix —> uterus —> oviduct
D. urethra —> uterus —> cervix —> fallopian tube
E. cervix —> fallopian tube —> vagina —> uterus
83. What two hormones influence the development of the secondary sexual characteristics of the female?
A. testosterone and estrogen
B. progesterone and estrogen
C. androgen and estrogen
D. testosterone and progesterone
E. FSH and cortisol
84. Menopause refers to
A. the menstrual phase.
B. premenstrual phase.
C. a time when men pause.
D. cessation of menstruation.
E. onset of menstruation.
85. Which of the following is NOT related to breast structure and function?
A. alveoli
B. prolactin
C. colostrum
D. areola
E. fimbriae
86. Female birth control pills act by inhibiting the production of
A. ACTH and LH.
B. TSH and FSH.
C. ACTH and LTH.
D. FSH and LH.
E. estrogen and progesterone.
87. Milk production is triggered in breasts after several days of ____ production by the ____.
A. prolactin, hypothalamus
B. prolactin, anterior pituitary
C. oxytocin, hypothalamus
D. oxytocin, anterior pituitary
E. estrogen, ovaries
88. Which of the following is NOT true after a person has had a vasectomy?
A. Bulbourethral glands are not affected by the operation.
B. The vas deferens still transports sperm to the urethra.
C. The interstitial cells can still release hormones.
D. The semen will not contain sperm.
E. The oviduct will not be affected.
89. Which is NOT a barrier method of birth control?
A. condom
B. cervical cap
C. diaphragm
D. douche
90. The medication known as mifepristone or RU-486
A. kills sperm as they enter the female reproductive tract.
B. blocks the progesterone receptors of cells in the uterine lining and causes menstruation.
C. prevents an egg from maturing and being released–essentially a stronger regular birth control pill.
D. destroys the embryo which in turn causes a spontaneous miscarriage.
E. prevents development of a uterine lining.
91. Which of the following would NOT result in infertility?
A. Egg is fertilized but does not implant.
B. Egg is fertilized and implants.
C. Egg is not fertilized due to low sperm count.
D. endometriosis.
E. Egg is not ovulated.
92. Male infertility is on the increase and estrogens in the environment (ecoestrogens) are considered a possible
culprit because
A. any estrogen in a male's system tends to destroy the testicular tissue.
B. estrogen is a female hormone only and therefore depresses male traits including sperm production.
C. ecoestrogens bind to receptors and prevent natural estrogens from binding normally.
D. endometriosis in the female reproductive tract.
93. Viruses are responsible for
A. AIDS.
B. chlamydia.
C. gonorrhea.
D. syphilis.
94. The AIDS virus attacks
A. helper T lymphocytes.
B. Sertoli cells.
C. B lymphocytes.
D. interstitial cells.
E. follicle cells.
95. The cure for AIDS is
A. vaccination.
B. changing the diet.
C. antibiotic treatment.
D. antiviral drugs.
E. None of these.
96. A liver-damaging disease more likely to be contracted from sexual contact than AIDS is
A. HIV.
B. hepatitis.
C. chlamydia.
D. herpes.
E. gonorrhea.
97. If a person had recently undergone major doses of antibiotics accompanying surgery, which STD(s) would
likely be collaterally treated?
A. AIDS
B. syphilis
C. genital warts
D. hepatitis
E. all of the choices are correct
98. The cure for herpes is
A. vaccination.
B. changing the diet.
C. antibiotic treatment.
D. antiviral drugs.
E. None of these.
99. The cure for gonorrhea is
A. vaccination.
B. changing the diet.
C. antibiotic treatment.
D. antiviral drugs.
E. None of the choices are effective.
100. Blindness in newborn infants occurs when the mother
A. is overweight.
B. has gonorrhea.
C. has a yeast infection.
D. has chlamydia.
E. uses birth control pills without a prescription.
101. Syphilis is caused by
A. Candida albicans.
B. Trichomonas vaginalis.
C. a virus.
D. Treponema pallidum.
E. genital warts.
102. Parthenogenesis is found in all of the following EXCEPT
A. fish.
B. flatworms.
C. primates.
D. crustaceans.
103. Gonads are
A. absent in sponges.
B. are organs of gamete production.
C. temporary in hydras and cnidarians.
D. All of the choices are true regarding gonads.
104. Copulation mechanisms in which of the following are incorrectly matched?
A. crayfish–modified swimmerettes
B. octopuses–arm
C. sharks–pelvic fin
D. birds–penis
105. Metamorphosis includes which of the following?
A. a larval stage able to seek its own food independently of the parent
B. may include several larval stages
C. a pupa stage within a cocoon
D. all of the choices characterize metamorphosis
106. A procedure for the human male to not be able to produce semen with functional sperm is a (an)
A. epididyectomy.
B. vasectomy.
C. transurethral resection of the prostate.
D. all of the choices.
107. Fluid from which of the following make up semen?
A. sperm
B. prostate fluid
C. secretions from the bulbourethral glands
D. all of the choices make up semen
108. Female infertility may be due to which of the following?
A. blocked fallopian tubes
B. endometriosis
C. failure to ovulate
D. all of the choices are related to female infertility
109. All animals must participate in copulation in order to reproduce.
True False
110. A male's testosterone levels will begin to decline in his thirties.
True False
111. The penis becomes erect when spongy spaces within it become filled with blood.
True False
112. The function of acrosomal enzymes produced by sperm cells is to provide energy for the movement of the
sperm tail.
True False
113. Hormonal regulation in the male reproductive system is ultimately the responsibility of the hypothalamus
in the brain.
True False
114. Implantation of the embryo occurs in the endometrial lining of the vagina.
True False
115. In the uterine cycle, the first hormone to be active in building up the endometrium is progesterone.
True False
116. The luteal phase of the ovarian cycle is characterized by FSH stimulating the corpus luteum and increased
production of progesterone.
True False
117. The placenta is the organ of nourishment for the mammalian fetus and is formed of tissues from both the
mother and the fetus.
True False
118. Menopause normally occurs around age 60, when women stop menstruating.
True False
119. Implantation of the embryo in the endometrium is the first step in the establishment of the pregnancy.
True False
120. The hormone produced by the corpus luteum is progesterone.
True False
121. Syphilis is a sexually transmitted disease caused by a virus.
True False
122. A frequent cause of sterility or infertility is pelvic inflammatory disease, which can block the passage of
gametes in the male or female reproductive tract.
True False
123. The ultimate in caring for offspring is viviparity.
True False
124. Lunar cycles appear to be the signal that causes aquatic animals that practice fertilization externally to
release their eggs and sperm in water at certain times.
True False
125. Discuss how internal fertilization and the production of shelled eggs were important in the development of
animals capable of living on land.
126. Describe the differences between asexual and sexual reproduction, and conditions under which each would
be advantageous and disadvantageous.
127. Describe the path taken by sperm cells as they develop and leave the body.
128. Describe the path taken by egg cells as they develop and leave the body (unfertilized).
129. Describe the occurrences of the menstrual cycle, focusing on the ovarian cycle.
130. Describe the occurrences of the menstrual cycle, focusing on the uterine cycle.
131. Describe the characteristics and treatment of syphilis.
132. Describe the characteristics and treatment of gonorrhea.
133. Birds never developed an internal placental system but are confined to laying eggs. Consider all of the
physiological burdens and limitations imposed by bearing live young, and consider all of the adaptations of
birds for flight. Given that birds arose from dinosaur-like ancestors that also laid eggs, but birds managed to
evolve a high metabolism and other advanced features, describe one physiological reason that probably limits
birds from ever evolving viviparity.
134. Beef farmers don't need half a herd of dangerous bulls, but about half the calves born are male. Why does
castrating young male calves cause them to grow in female proportions with more tender meat? What are the
hormonal effects that do or do not occur?
135. Contraception (preventing conception) and birth control (preventing live birth) are not quite the same. To
which category do "morning-after" pills and mifepristone (RU-486) belong, and why?
Chapter 43 KEY
1. A
2. B
3. D
4. E
5. D
6. D
7. E
8. B
9. C
10. C
11. C
12. A
13. E
14. B
15. E
16. E
17. E
18. D
19. D
20. C
21. D
22. E
23. C
24. C
25. B
26. D
27. C
28. B
29. C
30. A
31. B
32. D
33. B
34. D
35. D
36. A
37. C
38. E
39. D
40. A
41. D
42. B
43. C
44. A
45. B
46. C
47. E
48. D
49. C
50. B
51. E
52. E
53. E
54. E
55. C
56. D
57. A
58. B
59. E
60. D
61. A
62. C
63. C
64. C
65. E
66. E
67. A
68. A
69. D
70. C
71. C
72. B
73. B
74. E
75. B
76. C
77. E
78. C
79. E
80. D
81. B
82. C
83. B
84. D
85. E
86. D
87. B
88. B
89. D
90. B
91. B
92. C
93. A
94. A
95. E
96. B
97. B
98. E
99. C
100. B
101. D
102. C
103. D
104. D
105. D
106. B
107. D
108. D
109. FALSE
110. FALSE
111. TRUE
112. FALSE
113. TRUE
114. FALSE
115. FALSE
116. FALSE
117. TRUE
118. FALSE
119. TRUE
120. TRUE
121. FALSE
122. TRUE
123. TRUE
124. TRUE
125. Answers will vary.
126. Answers will vary.
127. Answers will vary.
128. Answers will vary.
129. Answers will vary.
130. Answers will vary.
131. Answers will vary.
132. Answers will vary.
133. Answers will vary.
134. Answers will vary.
135. Answers will vary.