Question 1

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

Accepted Answer

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. 
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. D

Question 2

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?

Accepted Answer

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 
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 C

Question 3

Which of the following is FALSE regarding bird reproduction?

Accepted Answer

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. 
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. B

Question 4

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

Accepted Answer

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. 
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 5

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

Accepted Answer

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. 
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.

Question 6

All vertebrates rely exclusively on sexual reproduction.

Accepted Answer

A) true 
B) false 
A) true 
B) false

Question 7

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

Accepted Answer

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. 
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 8

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

Accepted Answer

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

Question 9

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

Accepted Answer

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. 
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 10

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?

Accepted Answer

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. 
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 11

Following spermatogenesis,sperm are stored in the

Accepted Answer

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

Question 12

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

Accepted Answer

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

Question 13

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?

Accepted Answer

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

Question 14

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

Accepted Answer

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. 
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 15

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

Accepted Answer

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

Question 16

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

Accepted Answer

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

Question 17

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

Accepted Answer

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 
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 18

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

Accepted Answer

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

Question 19

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

Accepted Answer

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. 
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

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?

Accepted Answer

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. 
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.

Exam 48: Animal Reproduction

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

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?

Which of the following is FALSE regarding bird reproduction?

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

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

All vertebrates rely exclusively on sexual reproduction.

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

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

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

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?

Following spermatogenesis,sperm are stored in the

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

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?

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

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

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

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

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

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

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?

Biology and the Tree of Life

Water and Carbon: the Chemical Basis of Life

Protein Structure and Function

Nucleic Acids and the Rna World

An Introduction to Carbohydrates

Lipids, membranes, and the First Cells

Inside the Cell

Cell-Cell Interactions

Cellular Respiration and Fermentation

Photosynthesis

The Cell Cycle

Meiosis

Mendel and the Gene

Dna and the Gene: Synthesis and Repair

How Genes Work

Transcription, RNA Processing, and Translation

Control of Gene Expression in Bacteria

Control of Gene Expression in Eukaryotes

Analyzing and Engineering Genes

Genomics

Principles of Development

An Introduction to Animal Development

An Introduction to Plant Development

Evolution by Natural Selection

Evolutionary Processes

Speciation

Phylogenies and the History of Life

Bacteria and Archaea

Protists

Green Algae and Land Plants

Fungi

An Introduction to Animals

Protostome Animals

Deuterostome Animals

Viruses

Plant Form and Function

Water and Sugar Transport in Plants

Plant Nutrition

Plant Sensory Systems, signals, and Responses

Plant Reproduction

Animal Form and Function

Water and Electrolyte Balance in Animals

Animal Nutrition

Gas Exchange and Circulation

Electrical Signals in Animals

Animal Sensory Systems and Movement

Chemical Signals in Animals

The Immune System in Animals

An Introduction to Ecology

Behavioural Ecology

Population Ecology

Community Ecology

Ecosystems

Biodiversity and Conservation Biology

Filters

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