Deck 46: Animal Reproduction

Question 1

Evidence that parthenogenic whiptail lizards are derived from sexually reproducing ancestors includes

A)the requirement for male-like behaviors in some females before their partners will ovulate.
B)the development and then regression of testes prior to sexual maturation.
C)the observation that all of the offspring are haploid.
D)dependence on favorable weather conditions for ovulation to occur.
E)the persistence of a vestigial penis among some of the females.

Answer 1

A

Question 2

Environmental cues that influence the timing of reproduction generally do so by

A)increasing the body temperature.
B)providing access to water for external fertilization.
C)increasing ambient temperature to that which is comfortable for sex.
D)direct effects on gonadal structures.
E)direct effects on hormonal control mechanisms.

Answer 2

E

Question 3

Like many other fishes, bluehead wrasses utilize harem mating as they reproduce sexually, but unlike most fish,

A)they are simultaneous hermaphrodites.
B)they function without any signaling by steroid hormones.
C)they undergo a prolonged diapause during low tide.
D)their offspring can be either haploid or diploid.
E)large females morph into reproductively competent males.

Answer 3

E

Question 4

For water fleas of the genus Daphnia, switching from a pattern of asexual reproduction to sexual reproduction coincides with

A)environmental conditions becoming more favorable.
B)greater abundance of food resources.
C)periods of temperature or food stresses.
D)completion of puberty.
E)exhaustion of an organism's supply of eggs.

Question 5

Sexual reproduction patterns include the example of

A)fragmentation.
B)budding.
C)hermaphroditism.
D)parthenogenesis.
E)fission.

Question 6

Organisms with a reproductive pattern that produce shelled amniotic eggs generally

A)end up having a higher embryo mortality rate than do organisms with unprotected embryos.
B)invest most of their reproductive energy in the embryonic and early postnatal development of their offspring.
C)invest more energy in parenting than do placental animals.
D)produce more gametes than do those animals with external fertilization and development.
E)lower their embryo mortality rate to less than one in a thousand.

Question 7

In close comparisons, external fertilization often yields more offspring than does internal fertilization, but internal fertilization offers the advantage that

A)it is the only way to ensure the survival of the species.
B)it requires less time and energy to be devoted to reproduction.
C)the smaller number of offspring produced often receive a greater amount of parental investment.
D)it permits the most rapid population increase.
E)it requires expression of fewer genes and maximizes genetic stability.

Question 8

Regeneration, the regrowth of lost body parts, normally follows

A)all types of asexual reproduction.
B)all types of sexual reproduction.
C)fission.
D)fragmentation.
E)parthenogenesis.

Question 9

Which statement is False concerning reproduction in invertebrate animals?

A)Separate sexes are not observed among any invertebrates.
B)Some have both sexes within one individual organism.
C)Some utilize external fertilization.
D)Some utilize internal fertilization.
E)None of the invertebrates have structures that store sperm.

Question 10

A cloaca is an anatomical structure found in many nonmammalian vertebrates, which functions as

A)a specialized sperm-transfer device produced by males.
B)a common exit for the digestive, excretory, and reproductive systems.
C)a region bordered by the labia minora and clitoris in females.
D)a source of nutrients for developing sperm in the testes.
E)a gland that secretes mucus to lubricate the vaginal opening.

Question 11

Internal and external fertilization both

A)produce zygotes.
B)occur only among invertebrates.
C)occur only among terrestrial animals.
D)depend on the use of intromittent copulatory organs.
E)occur only among birds.

Question 12

One of the evolutionary "enigmas," or unsolved puzzles, of sexual reproduction is due to the fact that

A)sexual reproduction allows for more rapid population growth than does asexual reproduction.
B)only half of the offspring from sexually reproducing females are also females.
C)asexual reproduction produces offspring of greater genetic variety.
D)sexual reproduction is completed more rapidly than asexual reproduction.
E)asexual reproduction is better suited to environments with extremely varying conditions.

Question 13

Sexual reproduction

A)allows animals to conserve resources and reproduce only during optimal conditions.
B)can produce diverse phenotypes that may enhance survival of a population in a changing environment.
C)yields more numerous offspring more rapidly than is possible with asexual reproduction.
D)enables males and females to remain isolated from each other while rapidly colonizing habitats.
E)guarantees that both parents will provide care for each offspring.

Question 14

All individuals of a particular species of whiptail lizards are females. Their reproductive efforts depend on

A)fertilization of their eggs by males of other lizard species.
B)gonadal structures that only undergo mitosis.
C)meiosis followed by a doubling of the chromosomes in eggs.
D)budding prior to the development of a sexual phenotype.
E)fragmentation via autolysis.

Question 15

Chemical signals exchanged between potential reproductive partners are called

A)hormones.
B)pheromones.
C)paracrine signals.
D)cytokines.
E)gametes.

Question 16

Genetic mutations in asexually reproducing organisms lead to more evolutionary change than do genetic mutations in sexually reproducing ones because

A)asexually reproducing organisms, but not sexually reproducing organisms, pass all mutations to their offspring.
B)asexually reproducing organisms devote more time and energy to the process of reproduction than do sexually reproducing organisms.
C)sexually reproducing organisms can produce more offspring in a given time than can sexually reproducing organisms.
D)more genetic variation is present in organisms that reproduce asexually than is present in those that reproduce sexually.
E)asexually reproducing organisms have more dominant genes than organisms that reproduce sexually.

Question 17

An advantage of asexual reproduction is that

A)asexual reproduction allows the species to endure long periods of unstable environmental conditions.
B)asexual reproduction enhances genetic variability in the species.
C)asexual reproduction enables the species to rapidly colonize habitats that are favorable to that species.
D)asexual reproduction produces offspring that respond effectively to new pathogens.
E)asexual reproduction allows a species to readily rid itself of harmful mutations.

Question 18

Asexual reproduction results in greater reproductive success than does sexual reproduction

A)when pathogens are rapidly diversifying.
B)when a species has accumulated numerous deleterious mutations.
C)when there is some potential for rapid overpopulation.
D)when a species is expanding into diverse geographic settings.
E)when a species is in stable and favorable environments.

Question 19

If you observe vertebrate organisms with parthenogenetic reproduction, internal development of embryos, and the lack of parental care for its young, you should categorize these organisms as

A)earthworms.
B)lizards.
C)birds.
D)frogs.
E)mammals.

Question 20

Animals with reproduction dependent on internal fertilization need not have

A)any copulatory organs.
B)a receptacle that receives sperm.
C)behavioral interaction between males and females.
D)internal development of embryos.
E)haploid gametes.

Question 21

During human heterosexual (mutual)excitement, vasocongestion

A)occurs only in the penis.
B)occurs only in the testes.
C)occurs only in the clitoris.
D)occurs only in the upper vagina.
E)occurs in the clitoris, vagina, and penis.

Question 22

Increasing and holding the temperature of the scrotum by 2°C, near the normal body-core temperature, would

A)reduce the fertility of the man by impairing the production of gonadal steroid hormones.
B)reduce the fertility of the man by impairing spermatogenesis.
C)reduce the fertility of the man by impairing by abolishing sexual interest.
D)increase the fertility of the affected man by enhancing the rate of spermatogenesis.
E)have no effect on male reproductive processes.

Question 23

An oocyte released from a human ovary enters the oviduct as a result of

A)the beating action of the flagellum on the oocyte.
B)the force of the follicular ejection directing the oocyte into the oviduct.
C)the wavelike beating of cilia lining the oviduct.
D)movement of the oocyte through the pulsing uterus into the oviduct.
E)Peristaltic contraction of ovarian muscles.

Question 24

When female fruit flies mate with two different males on the same day,

A)the first male's sperm fertilizes all of the eggs.
B)the first male's sperm fertilizes most of the eggs.
C)the second male's sperm fertilizes most of the eggs.
D)the first and second males fertilize equal numbers of eggs.
E)none of the eggs become fertilized.

Question 25

Most flatworms, including parasitic liver flukes, are hermaphrodites where zygotes form as the result of

A)internal fertilization.
B)external fertilization.
C)parthenogenesis.
D)eggs and sperm mixing together in excreted feces.
E)eggs and sperm mixing together in wastewater.

Question 26

At the time of fertilization, the complete maturation of each oogonium has resulted in

A)one secondary oocyte.
B)two primary oocytes.
C)four secondary oocytes.
D)four primary oocytes.
E)four zygotes.

Question 27

Human sperm cells first arise in the

A)prostate gland.
B)vas deferens.
C)seminiferous tubules.
D)epididymis.
E)Sertoli cells.

Question 28

Among human males, both semen and urine normally travel along the

A)vas deferens.
B)urinary bladder.
C)seminal vesicle.
D)urethra.
E)ureter.

Question 29

A male's "primary" sex characteristics include

A)deepening of the voice at puberty.
B)embryonic differentiation of the seminal vesicles.
C)growth of skeletal muscle.
D)elongation of the skeleton prior to puberty.
E)onset of growth of facial hair at puberty.

Question 30

The junction of the upper vagina and the uterus is called the

A)fallopian tube.
B)clitoris.
C)oviduct.
D)labia majora.
E)cervix.

Question 31

Mature human sperm and ova are similar in that

A)they both have the same number of chromosomes.
B)they are approximately the same size.
C)they each have a flagellum that provides motility.
D)they are produced from puberty until death.
E)they are formed before birth.

Question 32

The moment of orgasm is characterized by

A)the ovulation of the oocyte from the ovary.
B)the release of sperm from the seminiferous tubules.
C)rhythmic contraction of many parts of the reproductive system.
D)increased synthesis and release of ovarian steroid hormones.
E)increased synthesis and release of testicular steroid hormones.

Question 33

Sperm cells are stored within human males in the

A)urethra.
B)prostate.
C)epididymis.
D)seminal vesicles.
E)bulbourethral gland.

Question 34

Females of many insect species, including honeybee queens, can store gametes shed by their mating partners in

A)their nests.
B)the abdominal tract.
C)the cloaca.
D)the uterus.
E)the spermatheca.

Question 35

The male and female structures that consist mostly of erectile tissue include

A)penis and clitoris.
B)vas deferens and oviduct.
C)testes and ovaries.
D)seminiferous tubules and hymen.
E)prostate and ovaries.

Question 36

In vertebrate animals, spermatogenesis and oogenesis differ, in that

A)oogenesis begins at the onset of sexual maturity, whereas spermatogenesis happens in embryonic development.
B)oogenesis produces four haploid cells, whereas spermatogenesis produces only one functional spermatozoon.
C)cytokinesis is unequal in oogenesis, whereas it is equal in spermatogenesis.
D)oogenesis ends at menopause, whereas spermatogenesis is finished before birth.
E)spermatogenesis is not completed until after fertilization occurs, but oogenesis is completed by the time a girl is born.

Question 37

Testosterone is synthesized primarily by the

A)sperm cells.
B)hypothalamus.
C)Leydig cells.
D)anterior pituitary gland.
E)seminiferous tubules.

Question 38

The surgical removal of the seminal vesicles would likely

A)cause sterility because sperm would not be produced.
B)cause sterility because sperm would not be able to exit the body.
C)greatly reduce the volume of semen.
D)enhance the fertilization potency of sperm in the uterus.
E)cause the testes to migrate back into the abdominal cavity.

Question 39

In humans, the follicular cells that remain behind in the ovary following ovulation become

A)ovarian endometrium shed at the time of menses.
B)a steroid-hormone synthesizing structure called the corpus luteum.
C)the thickened portion of the uterine wall.
D)swept into the fallopian tube.
E)the placenta, which secretes cervical mucus.

Question 40

Most of the noncellular fluid in ejaculated human semen is composed of

A)the secretions of the seminiferous tubules.
B)the secretions of the bulbourethral glands.
C)the secretions of the seminal vesicles.
D)the secretions of the prostate gland.
E)anticoagulant enzymes.

Question 41

Fertilization of human eggs usually takes place in the

A)ovary.
B)uterus.
C)vagina.
D)oviduct.
E)cervix.

Question 42

The primary function of the corpus luteum is to

A)nourish and protect the egg cell.
B)produce prolactin in the alveoli.
C)maintain progesterone and estrogen synthesis after ovulation has occurred.
D)stimulate the development of the mammary glands.
E)support pregnancy in the second and third trimesters.

Question 43

For normal human fertilization to occur,

A)many ova must be released.
B)the uterus must be enlarged.
C)only one sperm need penetrate one egg.
D)secretion of pituitary FSH and LH must decrease.
E)the secondary oocyte must implant in the uterus.

Question 44

The hormone progesterone is produced

A)in the pituitary and acts directly on the ovary.
B)in the uterus and acts directly on the pituitary.
C)in the ovary and acts directly on the uterus.
D)in the pituitary and acts directly on the uterus.
E)in the uterus and acts directly on the pituitary.

Question 45

Prior to ovulation, the steroid hormone secreted by the growing follicle is

A)LH.
B)FSH.
C)inhibin.
D)GnRH.
E)estradiol.

Question 46

The hypothalamic hormone that stimulates hormone secretion by the anterior pituitary gland is

A)LH.
B)FSH.
C)Inhibin.
D)GnRH.
E)estradiol.

Question 47

This embryonic hormone maintains progesterone and estrogen secretion by the corpus luteum through the first trimester of pregnancy:

A)luteinizing hormone (LH)
B)follicle-stimulating hormone (FSH)
C)progesterone
D)human chorionic gonadotropin (HCG)
E)gonadotropin-releasing hormone (GnRH)

Question 48

Which hypothalamic hormone triggers the secretion of FSH?

A)luteinizing hormone (LH)
B)follicle-stimulating hormone (FSH)
C)progesterone
D)human chorionic gonadotropin (HCG)
E)gonadotropin-releasing hormone (GnRH)

Question 49

Menopause is caused by

A)reduced synthesis of ovarian steroids despite high levels of gonadotropin hormones.
B)a decline in production of the gonadotropin hormones by the anterior pituitary gland.
C)wearing away of the uterine endometrium.
D)an increase in the blood supply to the ovaries.
E)a halt in the synthesis of gonadotropin-releasing hormone by the brain.

Question 50

The breakdown and discharge of the soft uterine tissues that occurs if no egg is fertilized is called

A)menstruation.
B)lactation.
C)fertilization.
D)menopause.
E)ovulation.

Question 51

A function-disrupting mutation in the progesterone receptor gene would likely result in

A)the absence of secondary sex characteristics.
B)the absence of pituitary gonadotropin hormones.
C)the inability of the uterus to support pregnancy.
D)enlarged and hyperactive uterine endometrium.
E)the absence of mammary gland development.

Question 52

A reliable "marker" that a pregnancy has initiated, and that is detectable in excreted urine, is

A)progesterone.
B)estrogen.
C)follicle-stimulating hormone.
D)chorionic gonadotropin.
E)hypothalamus releasing factors.

Question 53

This hormone is secreted directly from a structure in the brain:

A)testosterone
B)estradiol
C)progesterone
D)follicle stimulating hormone
E)gonadotropin-releasing hormone

Question 54

Ovulation is the follicular response to a burst of secretion of

A)LH.
B)progesterone.
C)inhibin.
D)prolactin.
E)estradiol.

Question 55

For the 10 days following ovulation in a nonpregnant menstrual cycle, the main source of progesterone is the

A)adrenal cortex.
B)anterior pituitary.
C)corpus luteum.
D)developing follicle.
E)placenta.

Question 56

In correct chronological order, the three phases of the ovarian cycle are

A)menstrual → ovulation → luteal
B)follicular → luteal → secretory
C)menstrual → proliferative → secretory
D)follicular → ovulation → luteal
E)proliferative → luteal → ovulation

Question 57

The primary difference between estrous and menstrual cycles is that

A)the endometrium shed by the uterus during the estrous cycle is reabsorbed but the shed endometrium is excreted from the body during the menstrual cycle.
B)behavioral changes during estrous cycles are much less apparent than those of menstrual cycles.
C)season and climate have less pronounced effects on estrous cycle than they do on menstrual cycles.
D)copulation normally occurs across the estrous cycle, whereas in menstrual cycles copulation only occurs during the period surrounding ovulation.
E)most estrous cycle are of much longer duration compared to menstrual cycles.

Question 58

In correct chronological order, the three phases of the uterine cycle are

A)menstrual → ovulation → luteal
B)follicular → luteal → secretory
C)menstrual → proliferative → secretory
D)follicular → ovulation → luteal
E)proliferative → luteal → ovulation

Question 59

A contraceptive pill that continuously inhibits the release of GnRH from the hypothalamus will

A)increase the production of estrogen and progesterone by the ovaries.
B)initiate ovulation.
C)reduce the secretion of gonadotropins from the anterior pituitary gland.
D)stimulate the secretion of LH and FSH from the posterior pituitary gland.
E)increase the flow phase of the menstrual cycle.

Question 60

A primary response by the Leydig cells in the testes to the presence of luteinizing hormone is an increase in the synthesis and secretion of

A)inhibin.
B)testosterone.
C)oxytocin.
D)prolactin.
E)progesterone.

Question 61

So-called "combination" birth-control pills function in contraception by

A)inhibiting the release of GnRH, FSH, and LH.
B)irritating the uterine lining so as to prevent implantation.
C)causing spontaneous abortions.
D)blocking progesterone receptors, so that pregnancy cannot be maintained.
E)binding to and inactivating any sperm that enter the oviduct.

Question 62

Which pair includes two contraceptive methods that are generally irreversible means to block gametes from moving to a site where fertilization can occur?

A)male condom and female condom
B)male condom and oral contraceptives
C)vasectomy and tubal ligation
D)coitus interruptus and rhythm method
E)diaphragm and subcutaneous progesterone implant

Question 63

The secretion of follicle stimulating hormone from the pituitary is reduced by

A)inhibin.
B)luteinizing hormone.
C)oxytocin.
D)prolactin.
E)vasopressin.

Question 64

Vasectomy

A)eliminates spermatogenesis.
B)eliminates testosterone synthesis.
C)prevents implantation of an embryo.
D)prevents sperm from exiting the male urethra.
E)prevents oocytes from entering the uterus.

Question 65

In male mammals, excretory and reproductive systems share

A)the testes.
B)the urethra.
C)the urinary duct.
D)the vas deferens.
E)the prostate.

Question 66

A thin layer of the developing embryo that secretes the hormone that keeps the corpus luteum functioning is

A)cervix.
B)endometrium.
C)amnion.
D)plasma membrane.
E)chorion.

Question 67

The use of birth-control pills (oral contraceptives)

A)reduces the incidence of ovulation.
B)prevents fertilization by keeping sperm and egg physically separated by a mechanical barrier.
C)prevents implantation of an embryo.
D)prevents sperm from exiting the male urethra.
E)prevents oocytes from entering the uterus.

Question 68

The "immunotolerance" of a pregnant woman toward her unborn child is the result of

A)the tenacity with which the unborn child's immune system counteracts the woman's immune system.
B)the relative quiescence of a pregnant woman's immune system compared to when she was not pregnant.
C)the complete physical separation from her cells and those of the unborn child.
D)the unborn child having enough of the woman's identity so as to escape detection as foreign.
E)modern medical intervention during every pregnancy.

Question 69

A high rate of metabolic activity is maintained in the pregnant uterus by

A)inhibin.
B)testosterone.
C)oxytocin.
D)prolactin.
E)progesterone.

Question 70

Among these contraception methods, which has the highest risk of accidental pregnancy?

A)diaphragm
B)condom
C)coitus interruptus
D)vasectomy
E)rhythm method

Question 71

Tubal ligation

A)reduces the incidence of ovulation.
B)prevents fertilization by preventing sperm from entering the uterus.
C)prevents implantation of an embryo.
D)prevents sperm from exiting the male urethra.
E)prevents oocytes from entering the uterus.

Question 72

Time-release progesterone implants function in contraception by

A)increasing the frequency of ovulation.
B)thickening the cervical and uterine mucus to impair sperm movement.
C)increasing gonadotropin secretion to abnormally high levels.
D)reducing libido.
E)activating inflammation responses in the uterus.

Question 73

For lactation to take place, __________ stimulates the synthesis of breast milk and __________ causes milk expulsion.

A)testosterone; dihydrotestosterone
B)estrogen; progesterone
C)cortisol; testosterone
D)prolactin; oxytocin
E)luteinizing hormone; follicle stimulating hormone

Question 74

The drug RU486 functions by

A)inhibiting release of gonadotropins from the pituitary.
B)blocking progesterone receptors in the uterus.
C)preventing release of the secondary oocyte from the ovary.
D)A and B
E)A, B, and C

Question 75

Which of the following is a True statement?

A)All mammals have menstrual cycles.
B)The endometrial lining is shed in menstrual cycles but reabsorbed in estrous cycles.
C)Estrous cycles occur more often than menstrual cycles.
D)Estrous cycles are not controlled by hormones.
E)Ovulation occurs before the endometrium thickens in estrous cycles.

Question 76

A woman in the final week of pregnancy who is given an injection of oxytocin would likely

A)undergo the loss of oxytocin receptors from her uterine smooth muscle cells.
B)stop secreting prostaglandins from the placenta.
C)undergo vigorous contractions of her uterine muscles.
D)increase the synthesis and secretion of progesterone.
E) be prevented from lactation.

Question 77

Which of the following is not properly paired?

A)seminiferous tubule-cervix
B)Sertoli cells-follicle cells
C)testosterone-estradiol
D)labia majora-scrotum
E)vas deferens-oviduct

Question 78

Which of the following characterizes parthenogenesis?

A)An individual may change its sex during its lifetime.
B)Specialized groups of cells grow into new individuals.
C)An organism is first a male and then a female.
D)An egg develops without being fertilized.
E)Both mates have male and female reproductive organs.

Question 79

Human fertility drugs increase the chance of multiple births, probably because they

A)enhance implantation.
B)stimulate follicle development.
C)mimic progesterone.
D)stimulate spermatogenesis.
E)prevent parturition.

Question 80

Labor contractions would be increased by the use of a synthetic drug that mimics the action of

A)inhibin.
B)luteinizing hormone.
C)oxytocin.
D)prolactin.
E)vasopressin.