Deck 48: Animal Reproduction

Question 1

What is the most likely reason the 1.5-mm body of Drosophila bifurca has sperm that are 6 cm long?

A)The female's vaginal cavity is very deep and has a convoluted pathway.
B)The male has no penis-just an opening-and the sperm must create its own connection from the male opening to the female vagina.
C)The egg of this species is highly resistant to penetration,and the longer sperm stores sufficient energy to burrow through the egg wall.
D)The sperm can fill the female's sperm storage area,thus blocking competing male sperm.

Answer 1

D

Question 2

Which of the following represents the correct sequence of events for sexual reproduction?

A)mitosis → zygote → meiosis → gametes → embryo
B)meiosis → zygote → mitosis → gametes → embryo
C)mitosis → gametes → meiosis → zygote → embryo
D)meiosis → gametes → mitosis → zygote → embryo
E)meiosis → gametes → zygote → mitosis → embryo

Answer 2

E

Question 3

Most clams reproduce by releasing gametes into the water,and two gametes must fuse for successful reproduction.Two populations of a single species of clams were both kept under natural light and temperature conditions.The first population was housed separately,one clam per tank.The second population was kept as a group in a single tank.During the normal mid-summer reproductive period,researchers counted an equal number of individuals releasing gametes in both populations.What hypothesis does this experiment disprove?

A)Pheromones are necessary for timing gamete release.
B)Competition for food induces a switch to sexual reproduction.
C)Light and temperature control gamete release.
D)Light and temperature control pheromone release.

Answer 3

A

Question 4

Which of the following correctly describes the reproduction of males in Daphnia?

A)Daphnia males are produced asexually from unfertilized eggs.
B)Daphnia males are produced sexually through fertilization of eggs,but are sterile from birth.
C)Daphnia males are produced from a pseudo-sexual union of two eggs.
D)Daphnia males are produced asexually,but are sterile from birth.

Question 5

In an animal that switches between sexual and asexual reproduction,when is sexual reproduction more likely to occur?

A)when conditions for survival are favourable
B)when conditions for survival are unfavourable
C)neither of the above

Question 6

Which of the following is a challenge to the hypothesis that certain species of animals produce an unusually large number of sperm in order to increase the probability of conception when females engage in multiple matings?

A)Female bats can eject the sperm of certain males after mating.
B)A female can actively choose which male mates with her last,thus increasing the odds of conception with that male's sperm.
C)Answers A and B both challenge this hypothesis.
D)None of the above answers challenges this hypothesis.

Question 7

On a submarine expedition to the ocean bottom,you discover a population of fish that uses a method of reproduction in which female offspring develop from unfertilized eggs.What type of reproduction is this?

A)sexual
B)budding
C)cloning
D)parthenogenesis
E)hermaphroditism

Question 8

Why does external fertilization typically occur much more often in aquatic animals than in terrestrial animals?

A)The gametes are hydrophobic,so they must be suspended in water to avoid clumping.
B)The gametes must be produced in large numbers,which can occur only in aquatic environments.
C)The gametes must be kept wet to avoid desiccation.
D)All of the above answers apply.
E)None of the above answers apply.

Question 9

Which of the following structures in females is analogous in function to the vas deferens in males?

A)urethra
B)oviduct
C)uterus
D)cervix
E)vagina

Question 10

Aquatic animals that rely on external fertilization for reproduction have a low probability of successful fertilization.Which one of the following is not used by aquatic animals to increase the success of external fertilization?

A)release of pheromones to synchronize gamete release
B)production of a large number of gametes
C)moving onto land for fertilization
D)elaborate courtship rituals to synchronize gamete release

Question 11

What makes sexually reproduced offspring genetically different from their parents?

A)genetic recombination during meiosis
B)fusion of haploid gametes from different parents during fertilization
C)genetic recombination during mitosis
D)both A and B
E)all of the above

Question 12

Asexual reproduction results in offspring that are genetically identical to their parent.What type of cell division occurs to generate this type of offspring?

A)mitosis
B)meiosis
C)A and B in combination
D)none of the above

Question 13

Which one of the following criteria is not required to induce Daphnia to switch from asexual to sexual reproduction?

A)water from crowded populations of Daphnia
B)the absence of males in the population
C)short day lengths
D)low food supply

Question 14

Secretions from which part of the human male anatomy produces molecules that stimulate smooth muscle contractions in the uterus of females?

A)prostate gland
B)seminal vesicles
C)bulbourethral gland
D)testes

Question 15

You are studying two species of birds,both of which form monogamous pairs (one male and one female).In species 1,you find that the eggs in a pair's nest are in fact almost always the offspring of that pair.In species 2,you are surprised to find that many of the eggs in a nest were actually fathered by males of neighboring pairs.Apparently,mating outside of monogamous pairings is widespread in species 2.Given this information,what would be the logical prediction to make before comparing testis size of males of the two species?

A)Testes of species 1 are larger than testes of species 2.
B)Testes of species 2 are larger than testes of species 1.
C)There is no relationship between this observation and the size of testes.

Question 16

If a woman is unable to release an egg,which of the following reproductive technologies would be best to use?

A)Intracytoplasmic sperm injection (ICSI)
B)Intrauterine insemination (IUI)
C)In vitro fertilization (IVF)

Question 17

All vertebrates rely exclusively on sexual reproduction.

A)true
B)false

Question 18

By what mechanism does a second male mating with a female gain an advantage in sperm competition in some insects?

A)The second male's sperm physically dislodge the first male's sperm and insert themselves in place.
B)The accessory fluids from the second male's semen is able to displace stored sperm from competing males.
C)The second male will have larger testes and so produce larger numbers of sperm.
D)Answers A and B are both correct.

Question 19

Which of the following correctly describes a difference between spermatogenesis and oogenesis?

A)Spermatogenesis results in four mature sperm cells,while oogenesis results in one mature egg cell.
B)Spermatogenesis results in one mature sperm cell,while oogenesis results in four mature egg cells.
C)In spermatogenesis,mitosis occurs twice and meiosis once,while in oogenesis,mitosis occurs once and meiosis twice.
D)Answers A and C are both correct.

Question 20

What is the most likely explanation for why Daphnia switch from asexual to sexual reproduction when certain environmental conditions deteriorate?

A)Sexual reproduction can produce more offspring faster than asexual reproduction,thus increasing the likelihood the species will survive hard times.
B)Although energetically expensive,sexual reproduction creates all genetically superior individuals that are more likely to withstand hard times.
C)Asexual reproduction is too energy intensive to maintain during hard times.
D)Sexual reproduction creates individuals that are more genetically diverse,thus increasing the likelihood of some members surviving hard times.

Question 21

Which of the following is the most likely explanation for the lack of a filter blocking the passage of alcohol between the maternal and fetal circulations in humans?

A)There has not been enough time to evolve such a barrier.
B)Such a barrier would probably also block important molecules that need to be passed to the fetus.
C)The maternal and fetal blood mix directly together in an area with many villi,so a barrier is impossible.
D)Alcohol has some positive effects on the fetus,so evolution has resulted in an intermediate level of filtering that blocks all but the worst abuses of alcohol.

Question 22

Figure 48.1
Based on the figure above,showing fetal and adult oxygen-hemoglobin saturation curves,which of the following conclusions is true?

A)Curve A represents the adult saturation curve.
B)Adult saturation occurs at lower partial pressures of oxygen than fetal saturation does.
C)At 50% saturation,fetal blood will have a higher affinity for oxygen than adult blood will.
D)As the partial pressure of oxygen increases,adult hemoglobin approaches saturation faster than fetal hemoglobin does.
E)Answers C and D are both true.

Question 23

Why are bird eggs more nutrient rich relative to those found in a human?

A)The nutrients must sustain development until hatching.
B)Birds have a longer gestation period than humans and so require more nutrients.
C)The development of a bird embryo is more complex than the development of a human embryo.
D)In order to form the calcium carbonate egg shell.

Question 24

What structure in female humans is analogous to the sensitive tissues of the penis?

A)clitoris
B)labia minora
C)labia majora
D)vagina
E)cervix

Question 25

A physician finds that a 16-year-old male patient,who has a very high-pitched voice and underdeveloped testes,has abnormally low levels of testosterone.What structure(s)might be the reason that this patient is producing such a low level of testosterone? 1. gonads
2) pituitary gland
3) adrenal gland
4) hypothalamus
5) thyroid gland

A)#1 only
B)#1 and #2 only
C)#1 and #2 and #3
D)#1 and #2 and #4
E)#1 and #3 and #5

Question 26

Following spermatogenesis,sperm are stored in the

A)prostate gland.
B)seminal vesicles.
C)epididymis.
D)van deferens.

Question 27

Which of the following hormones are secreted by a developing embryo during pregnancy in humans?

A)luteinizing hormone (LH)
B)progesterone
C)estradiol
D)human chorionic gonadotropin (hCG)

Question 28

Why has RU-486 been dubbed by some as "the abortion pill"?

A)It prevents the zygote from implanting in the uterus,thus the zygote never develops beyond a few cells in size.
B)It blocks certain hormonal actions that result in menstrual flow occurring after implantation.
C)It mimics testosterone,which interferes with GnRH synthesis and thus terminates the pregnancy after several days.
D)A negative feedback on the pituitary stimulates the release of too much luteinizing hormone that prevents proper blood vessel formation in the embryo.

Question 29

Which of the following is FALSE regarding bird reproduction?

A)The female can still lay eggs even when fertilization has not taken place.
B)After they are laid,bird eggs have the same amount of nutrients as a human egg.
C)Birds lay eggs and thus are oviparous.
D)Female birds only have one ovary.

Question 30

During the menstrual cycle,________ peaks first,________ peak next,and finally ________ surges.

A)estradiol;LH and progesterone;FSH
B)progesterone;LH and FSH;estradiol
C)estradiol;LH and FSH;progesterone
D)estradiol;LH and FSH;testosterone
E)testosterone;estradiol and FSH;progesterone

Question 31

An ectopic pregnancy occurs when a fertilized egg implants somewhere other than in the lining of the uterus.Usually it implants in the oviduct.Which of the following would be the most likely explanation for such a pregnancy being unsuccessful?

A)The orientation of the baby would be sideways.
B)Human chorionic gonadotropin (hCG)cannot be produced in the oviduct.
C)The lining of the oviduct is unable to support the developing fetus.
D)The necessary hormones cannot reach the developing fetus in the oviduct.

Question 32

Which of the following hormones would you use if you want to induce ovulation in a few days?

A)estradiol (estrogen)
B)progesterone
C)luteinizing hormones (LH)
D)human chorionic gonadotropin (hCG)

Question 33

What is the significance of using the concentrations of 5,25,and 100 ng/l of 17β-estradiol for the dose in this experiment?

A)These concentrations are similar to those found in many animals.
B)These concentrations are found in the environment.
C)These concentrations are effective,yet not lethal to the fish.
D)These concentrations are standard in toxicology assays.

Question 34

Which of the following best explains why androgen abuse among males may lead to decreased sperm production?

A)Androgens can instruct the pituitary to decrease secretion of luteinizing hormone.
B)Androgens stimulate the production of hormones that result in the exertion of negative feedback in the testes.
C)Androgens stimulate excessive growth of the male accessory organs (like the prostate gland),thus blocking the effective transfer of sperm through the reproductive tract.
D)Androgens stimulate the release of excessive amounts of luteinizing hormone that has a damaging effect on the testicular cells responsible for spermatogenesis.

Question 35

Which of the following hormones would you use if you want to induce ovulation right away?

A)estradiol (estrogen)
B)progesterone
C)luteinizing hormones (LH)
D)human chorionic gonadotropin (hCG)

Question 36

Which embryonic tissue is responsible for forming the membrane that can be found completely surrounding the embryo while in utero?

A)ectoderm
B)mesoderm
C)endoderm
D)epiderm

Question 37

Which of the following is NOT a true statement about puberty in humans in the United States?

A)On average,puberty occurs at a younger age now than it did 200 years ago.
B)On average,puberty occurs later in girls with larger fat stores than it does in thin girls.
C)Puberty is initiated by hormones from the hypothalamic-pituitary axis.
D)All of the above are true statements about puberty.
E)Only answers A and B are true.

Question 38

A pregnant woman comes into the hospital past her due date.The doctor decides it is time for the baby to be delivered.Before performing a cesarean section,the doctor wants to try to induce labour.Which of the following would she most likely inject?

A)estrogen
B)progesterone
C)luteinizing hormone (LH)
D)follicle-stimulating hormone (FSH)
E)oxytocin

Question 39

You are assigned to write the report to the Environment Canada to help them decide what level of 17ß-estradiol to permit in sewage output.You do not want to make the level any lower than necessary,because it requires substantial additional money for the extra treatment of sewage.What level of 17ß-estradiol would you suggest is safe to prevent feminization of fish?

A)2)5 ng/l
B)5 ng/l
C)12.5 ng/l
D)25 ng/l
E)100 ng/l