Unit 8 Quiz (The Reproductive System)

How many seminiferous tubules are found in each lobule?

1-3

How many seminiferous tubules are found in the lobules? A) 1-3 B) 50-100 C) 200-300 D) 500 or more E) Millions

1-3

Describe the stages of labor.

1. The stage of dilation is the time from the onset of labor to the complete dilation of the cervix. 2. The stage of expulsion is the time from complete cervical dilation to delivery. 3. The placental stage is the time after delivery of the offspring until the placenta is expelled.

During pregnancy stroke volume can increase by

30%

During pregnancy stroke volume can increase by A) 10% B) 20% C) 30% D) 40% E) 50%

30%

How many pairs of pharyngeal arches are there?

5

How is it possible for a baby to have type O blood if neither parent is type O?

A baby can have blood type O if each parent is heterozygous and has one i allele.

Zygote is

A diploid fertilized ovum

What is the histological difference between a morula and a blastocyst?

A morula is a solid ball of cells; a blastocyst consists of a rim of cells (trophoblast) surrounding a cavity (blastocyst cavity) and an inner cell mass.

The result of polyspermy in humans is ________.

A nonfunctional zygote

What is the genotype of a red-green color-blind female?

A red-green color-blind female has an XcXc genotype.

A couple whose blood types are A (IAi) and B (IBi) may have a child with which blood type?

A, B, AB, or O

If a child has B blood, and the mother has B blood, what is the possible genotype of the father?

A, B, AB, or O

If one parent has type A blood and one parent has type B blood, what blood type is possible for their child?

AB, A, B, or O

In a heterozygous individual for a certain trait, the dominant allele gives normal skin pigmentation. What is the masked, recessive trait in this individual?

Albinism

Which of the following is a breast-feeding benefit for infants? Beneficial cells Beneficial molecules Decreased incidence of diseases later in life Enhancement of intellectual and neurological development All of these are breast-feeding benefits

All of these are breast-feeding benefits

Which of the following is a function of the hormone corticotropin-releasing hormone? Maintain endometrium of uterus during pregnancy Help prepare mammary glands for lactation Establish the timing of birth Increase flexibility of the pubic symphysis All of these are functions of CRH

All of these are functions of CRH

This exam is performed between 14-16 weeks gestation and is used to detect genetic abnormalities.

Amniocentesis

What information can be provided by amniocentesis?

Amniocentesis is used primarily to detect genetic disorders, but it also provides information concerning the maturity (and survivability) of the fetus.

This develops from the epiblast and carries a protective fluid.

Amnion

This develops from the epiblast and carries a protective fluid. A) Cytotrophoblast B) Yolk sac C) Exocoelomic membrane D) Amnion E) Lacunae

Amnion

Chromosome #15 is considered what type of chromosome?

An Autosome

What surface structures are anterior to the vaginal opening?

Anterior to the vaginal opening are the mons pubis, clitoris, prepuce, and external urethral orifice.

What are the results of embryonic folding?

As a result of embryonic folding, the embryo curves into a C-shape, various organs are brought into their eventual adult positions, and the primitive gut is formed.

What is the outcome of meiosis I?

As a result of meiosis I, the number of chromosomes in each cell is reduced by half.

Which structure consists of a primary oocyte that is surrounded by several layers of cuboidal cells called granulosa? A B C F H

B

Which structure in the figure secretes seminal plasmin, proteolytic enzymes like pepsinogen and lysozyme, and citric acid? Male Genitalia (Points : 1) C K B G L

B

Recessive genes are usually expressed in humans only when ________.

Both alleles are exactly the same, or homozygous

Which condition is a malpresentation in which the fetal buttocks or lower limbs present into the maternal pelvis?

Breech Presentation

This structure attaches the ovaries and the uterus to the pelvic wall. A) Broad ligament B) Mesovarium C) Ovarian ligament D) Suspensory ligament E) Hilum

Broad ligament

These are located inferior to the prostate on either side of the membranous urethra within the deep muscles of the perineum.

Bulbourethral Gland

These are located inferior to the prostate on other side of the membranous urethra within the deep muscles of the perineum. A) Bulbourethral glands B) Seminal vesicles C) Ejaculatory ducts D) Urethral ducts E) Prostate

Bulbourethral glands

This hormone is secreted by nonpregnant women from neurosecretory cells in the hypothalamus.

CRH

A Pap smear is a test performed to detect

Cancer of the Cervix

This is a series of functional changes that sperm go through when they are in the female reproductive tract.

Capacitation

This is a series of functional changes that sperm go through when they are in the female reproductive tract. A) Acrosomal reaction B) Maturation C) Fertilization D) Capacitation E) Polyspermy

Capacitation

What is capacitation?

Capacitation is the group of functional changes in sperm that enable them to fertilize a secondary oocyte, which occur after the sperm have been deposited in the female reproductive tract.

The reason recessive genetic disorders are more frequent than disorders inherited as dominant is that ________.

Carriers may pass them on to their offspring, unaware that they are carriers

This is the portion of the uterus that opens into the vagina.

Cervix

This is the portion of the uterus that opens into the vagina. A) Urethra B) Cervix C) Uterine tubes D) Inguinal canal E) Ovaries

Cervix

CVS is taking cells from where?

Chorion

This will become the primary structure for exchange of material between the mother and the fetus.

Chorionic Villi of the Placenta

What is line "G" pointing to? Chorionic villi Amnion Umbilical vein Umbilical artery Amnionic capillary bed

Chorionic villi

Why is the development of chorionic villi important?

Chorionic villi help to bring the fetal and maternal blood vessels into close proximity.

This will become the primary structure for exchange of material between the mother and the fetus. A) Chorionic villi of the placenta B) Amnion C) Amnionic fluid D) Embryonic disc E) Endoderm

Chorionic villi of the placenta

What types of cells line the uterine tubes?

Ciliated columnar epithelial cells and nonciliated (peg) cells with microvilli line the uterine tubes.

What event marks the beginning of the stage of expulsion?

Complete dilation of the cervix marks the onset of the stage of expulsion.

Which term includes all structures that develop from a zygote: the embryo, the embryonic placenta and its associated membranes?

Conceptus

Estrogen and progesterone maintain the integrity of the uterine lining and prepare the mammary glands to secrete milk. Which structure makes this possible during the first three months of pregnancy?

Corpus Luteum

Which structure has a portion removed in a vasectomy? A D E G I

D

This structure helps regulate the temperature of the testes

Dartos Muscle

This is the portion of the endometrium that lies between the embryo and the stratum basalis.

Decidua Basalis

This is the portion of the endometrium that lies between the embryo and the stratum basalis. A) Decidua basalis B) Decidua capsularis C) Decidua parietalis D) Lamina propria E) Adventitia

Decidua basalis

Clubfeet is an example of which condition?

Deformation

Which condition is a developmental abnormality due to mechanical forces that mold a part of the fetus over a prolonged period of time?

Deformation

Each somite may differentiate into a

Dermatome

In male embryos, this hormone is responsible for the development of the urethra, prostate, and external genitals.

Dihydrotestosterone

In infants this connects the umbilical vein to the inferior vena cava.

Ductus Venosus

Which hormone is detected by early pregnancy tests?

Early pregnancy tests detect elevated levels of human chorionic gonadotropin (hCG).

This is formed by the union of the duct from the seminal vesicle and the ampulla of the vas deferens.

Ejaculatory Duct

This is formed by the union of the duct from the seminal vesicle and the ampulla of the vas deferens. A) Urtethra B) Spermatic cord C) Inguinal canal D) Ejaculatory duct E) Prostate

Ejaculatory duct

Which condition is also called morning sickness?

Emesis Gravidarum

Which of the following is a function of the hormone corticotropin-releasing hormone? Maintain endometrium of uterus during pregnancy Help prepare mammary glands for lactation Establish the timing of birth Increase flexibility of the pubic symphysis All of these are functions of CRH

Establish the timing of birth

The major hormone secreted from granulosa cells is

Estrogen

How does the reproductive system affect the skeletal system?

Estrogen causes epiphyseal plates of both to close, ending growth in height.

Describe the roles of estrogens and progesterone.

Estrogens stimulate the growth, development and maintenance of the female reproductive structures. They stimulate the development of female secondary sex traits including the development of breasts and the pattern deposition of subcutaneous body fat. Estrogens cause the build up of the endometrial lining that prepares the uterus for implantation of the embryo. Estrogens also stimulate protein synthesis. Progesterone works with estrogens to prepare the endometrium for implantation and to prepare the breasts for milk production. Progesterone is critical to maintaining the endometrium throughout a pregnancy.

During which stage of labor is the fetus delivered?

Expulsion Stage

Which line represents the opening from the uterus to the vagina? E F G H None of these choices

F

Which structure in the figure is the corpus spongiosum penis? F D C E G

F

Describe the positive feedback loop involved in ovulation.

FSH and LH promote follicular development, thus increasing estrogen production. High levels of estrogen during the late preovulatory phase stimulate release of GnRH from the hypothalamus. GnRH promotes release of more FSH and LH from the anterior pituitary. Peak levels of LH trigger ovulation

Fertilization normally occurs within which structure?

Fallopian Tube

The structures that receive the ovulated oocyte, providing a site for fertilization, are called the ________.

Fallopian Tubes

Fertilization normally occurs within which structure? A) Ovary B) Fallopian tube C) Ovarian ligament D) Body of uterus E) Vagina

Fallopian tube

True or False: A pregnancy test involves antibodies that detect GH levels in a woman's blood or urine.

False

True or False: FSH and LH directly promote development of the uterine endometrium

False

True or False: Ovarian follicles contain mature eggs.

False

True or False: The adenohypophyseal hormone that triggers ovulation is estrogen.

False

True or False: The hormone oxytocin combines with enzymes in semen to enhance sperm motility.

False

True or False: The prostate atrophies as a man ages, and it usually causes no health problems.

False

Which changes in pregnancy have an effect on the ability to exercise?

Fatigue, morning sickness, weight gain and posture differences increase energy need, and loss of joint stability.

Where does fertilization usually occur?

Fertilization most often occurs in the ampulla of the uterine tube.

Which condition is one of the most common causes of mental retardation and the most common preventable cause of birth defects in the United States?

Fetal Alcohol Syndrome

How does mid-fetal weight compare to end-fetal weight?

Fetal weight doubles between the midfetal period and birth.

Menarche is the

First Menses

What is the significance of gastrulation?

Gastrulation converts a bilaminar embryonic disc into a trilaminar embryonic disc.

When phenotype can be drastically different depending on parental origin it is called:

Genomic Imprinting

What is the term used to describe the age of an embryo or fetus calculated from the presumed first day of the last normal menstrual period?

Gestational Age

Which hormone controls the release of anterior pituitary gonadotropins?

GnRH

__________ hormone, secreted by the __________ , controls the ovarian and uterine cycles. A) FSH, anterior pituitary B) LH, anterior pituitary C) GnRH, hypothalamus D) HGH, hypothalamus E) Estrogens, ovaries

GnRH, hypothalamus

What traits are transmitted by complex inheritance?

Hair color, height, body build, and skin color, among others, are traits passed on by complex inheritance.

Two alleles expressing exactly the same information for a trait are designated as ________.

Homozygous

In humans, separation of the cells at the two-cell state following fertilization may lead to the production of twins, which in this case would be ________.

Identical

In which phase of the uterine cycle does implantation occur?

Implantation occurs during the secretory phase of the uterine cycle.

What are the distinguishing features of incomplete dominance?

In incomplete dominance, neither member of an allelic pair is dominant; the heterozygote has a phenotype intermediate between the homozygous dominant and the homozygous recessive phenotypes.

Sickle-cell disease is an example of what mode of inheritance?

Incomplete Dominance

This hormone inhibits the release of FSH from the pituitary gland.

Inhibin

A Barr body is what?

Is an Inactivated X Chromosome

Which term describes the chromosomal characteristic of an individual presented as a systematic arrangement of pairs of metaphase chromosomes arranged by size?

Karyotype

Which condition gives rise to individuals that are: somewhat mentally disadvantaged, sterile males with undeveloped testes, scant body hair, and enlarged breasts?

Klinefelter's Syndrome

Which condition is a sex chromosome aneuploidy, usually due to trisomy XXY?

Klinefelter's Syndrome

This hormone stimulates Leydig cells to secrete testosterone.

LH

This hormone stimulates Leydig cells to secrete testosterone. A) GnRH B) LH C) FSH D) DHT E) None of the above

LH

This hormone triggers ovulation.

LH

This hormone triggers ovulation. A) GnRH B) LH C) FSH D) Estrogen E) Progesterone

LH

What surface structures are lateral to the vaginal opening?

Lateral to the vaginal opening are the labia minor and labia majora.

These cells secrete testosterone.

Leydig Cells

These cells secrete testosterone. A) Sertoli cells B) Spermatogenic cells C) Leydig cells D) Oogonia E) Chief cells

Leydig cells

The constancy of the chromosome number from one cell generation to the next is maintained through ________.

Meiosis

Anterior to the vagina and urethral openings is the

Mons Pubis

Anterior to the vagina and urethral openings is the A) Labia majora B) Labia minor C) Mons pubis D) Cervical sphincter E) Labial frenulum

Mons pubis

What happens to most ovarian follicles?

Most ovarian follicles undergo atresia (degeneration).

Skene's glands secrete

Mucus

Female reproductive system arises from

Mullerian ducts

This is a permanent change in an allele.

Mutation

In a heterozygous individual for a certain trait, the dominant allele gives polydactyly. What is the masked, recessive trait in this individual?

Normal Digits

In a heterozygous individual for a certain trait, the dominant allele gives Huntington's disease. What is the masked, recessive trait in this individual?

Normal Nervous System

During fetal development these cells give rise to primary oocytes.

Oogonia

What structures in the ovary contain endocrine tissue?

Ovarian follicles and corpus luteum

Which hormones are secreted by the ovarian follicle?

Ovarian follicles secrete estrogens.

This is a principle hormone that releases milk into the mammary ducts.

Oxytocin

This is a principle hormone that releases milk into the mammary ducts. A) Prolactin B) PIH C) PRH D) Oxytocin E) GnRH

Oxytocin

What hormone regulates the ejection of milk?

Oxytocin regulates the ejection of milk.

What are the functions of oxytocin?

Oxytocin stimulates contractions of the uterus during delivery of a baby and causes the milk ejection reflex.

This is composed of three cylindrical masses of erectile tissue each surrounded by a fibrous tissue.

Penis

This structure is composed of three cylindrical masses of erectile tissue each surrounded by a fibrous tissue. A) Testes B) Prostate C) Bladder D) Penis E) Urethra

Penis

Why are pharyngeal arches, clefts, and pouches important?

Pharyngeal arches, clefts, and pouches give rise to structures of the head and neck.

This is the ovarian phase between the end of menstruation and beginning of ovulation.

Preovulatory Phase

This is the ovarian phase between the end of menstruation and beginning of ovulation. A) Menstrual phase B) Preovulatory phase C) Proliferative phase D) Follicular phase E) Postovulatory phase

Preovulatory phase

How does the age of a primary oocyte in a female compare with the age of a primary spermatocyte in a male?

Primary oocytes are present in the ovary at birth, so they are as old as the woman. In males, primary spermatocytes are continually being formed from stem cells (spermatogonia) and thus are only a few days old.

Which of the terms below describes the beginning or first discernable indication of the development of an organ or structure? Conceptus Primordium Epigenesis Karyotype Fertilization age

Primordium

Labor cannot take place until all of this hormone's effects are diminished.

Progesterone

This is secreted by the corpus luteum after ovulation.

Progesterone

This is secreted by the corpus luteum after ovulation. A) Progesterone B) Relaxin C) LH D) FSH E) HGH

Progesterone

What hormones regulate the synthesis of milk?

Prolactin, estrogens, and progesterone regulate the synthesis of milk.

This is the uterine phase when the thickness of the endometrium doubles.

Proliferative Phase

This is the uterine phase when the thickness of the endometrium doubles. A) Menstrual phase B) Preovulatory phase C) Proliferative phase D) Follicular phase E) Postovulatory phase

Proliferative phase

Which condition is an infectious disease of childbirth resulting from an infection originating in the birth canal and affecting the mother's endometrium?

Puerperal Fever

What hormone increases the flexibility of the pubic symphysis and helps dilate the cervix of the uterus to ease delivery of the baby?

Relaxin increases the flexibility of the pubic symphysis and helps dilate the cervix of the uterus to ease delivery.

The straight tubules in the testis lead into the

Rete Testis

The straight tubules in the testis lead into Efferent ducts Afferent ducts Rete testis Ductus epididymis Epididymis

Rete testis

The straight tubules in the testis lead into the: A) Efferent ducts B) Afferent ducts C) Rete testis D) Ductus epididymis E) Epididymis

Rete testis

This structure protects and regulates the temperature of the testes A) Dartos muscle B) Cremaster muscle C) Tunica albuginea D) Scrotum E) Tunica vaginalis

Scrotum

What is produced by the ovaries?

Secondary oocytes, estrogen and progesterone

What is produced by the ovaries? A) Primary oocytes, insulin and estrogen B) Secondary oocytes, progesterone and cortisol C) Tertiary oocytes, insulin and estrogen D) Secondary oocytes, estrogen and progesterone E) Primary oocytes, estrogen and testosterone

Secondary oocytes, estrogen and progesterone

This lies posterior to the bladder and anterior to the rectum and secretes an alkaline, fructose filled fluid.

Seminal Vesicles

This structure lies posterior to the bladder and anterior to the rectum and secretes an alkaline, fructose-filled fluid. A) Prostate B) Bulbourethral gland C) Seminal vesicles D) Spongy urethra E) Prostatic urethra

Seminal vesicles

This structure is the site of sperm production.

Seminiferous Tubules

What is line "F" pointing to? Ductus epididymis Rete testis Efferent duct Afferent duct Seminiferous tubules

Seminiferous tubule

This structure is the site of sperm production. A) Vas deferens B) Seminiferous tubules C) Albuginea D) Epididymis E) Raphe

Seminiferous tubules

Which male cells secrete inhibin?

Sertoli cells secrete inhibin.

Symptoms of fetal alcohol syndrome include:

Slow growth before and after birth, thin upper lip and sunken nasal bridge, defective heart and other organs, and central nervous system damage.

Which structures develop from the somites?

Somites develop into skeletal muscles, connective tissue, and the vertebrae.

The function of the epididymis is

Sperm Maturation

The function of the epididymis is A) Sperm maturation B) Produce sperm C) Speratid storage D) Provide nutrition to sperm E) Absorption of calcium

Sperm maturation

Trace the path of a sperm cell from the site of its maturation to the site where it leaves the male body. Include descriptions of fluids added along that path.

Sperm mature in the epididymis. From there, they travel through the ductus (Vas) deferens through the abdominal cavity to the ampulla of the ductus deferens which merges with the duct of the seminal vesicle to form the ejaculatory duct. Sperm and the alkaline, fructose-rich fluid from the seminal vesicle move from the ejaculatory duct into the prostatic urethra, where they are mixed with a slightly acidic mucoid fluid from the prostate. Next the sperm and fluid pass through the membranous urethra and are mixed with additional alkaline secretions from the bulbourethral glands. The combination of sperm and secretions is called semen. The mixture travels through the penile urethra as it is ejaculated.

These cells may eventually become spermatozoa

Spermatagonia

These cells may eventually become spermatozoa A) Sertoli cells B) Sustentacular cells C) Spermatogenic cells D) Chief cells E) Speciation cells

Spermatogenic cells

This is the time from the onset of labor to the complete dilation of the cervix.

Stage of Dilation

This is the time from the onset of labor to the complete dilation of the cervix. A) Stage of dilation B) Stage of expulsion C) Placental stage D) Gestation E) Effacement

Stage of dilation

The primary action of combined oral contraceptives is to

Suppress FSH and LH, block implantation in the uterus, inhibit ovulation, and inhibit entry of sperm into the uterus.

Dominant alleles are so called because under most circumstances they ________.

Suppress the expression of other alleles

This attaches the ovaries and the uterus to the pelvic wall.

Suspensory Ligament

This ligament arises from the pubic symphysis in males.

Suspensory Ligament

This is any agent or influence that causes developmental defects in an embryo.

Teratogen

This hormone promotes spermatogenesis. A) Relaxin B) Testosterone C) Inhibin D) Estrogen E) Aldosterone

Testosterone

This hormone promotes the final step of spermatogenesis.

Testosterone

Which hormones inhibit secretion of FSH and LH by the anterior pituitary in males?

Testosterone inhibits secretion of LH, and inhibin inhibits secretion of FSH.

Describe the functions of testosterone.

Testosterone promotes the development and maintenance of male secondary sex characteristics, protein anabolism, development of sexual function (behavior, libido, spermatogenesis), and the male pattern of development during prenatal life.

Which male cells secrete testosterone?

The Leydig (interstitial) cells of the testes secrete testosterone.

Which gene is responsible for the development of the gonads into testes?

The SRY gene on the Y chromosome is responsible for the development of the gonads into testes.

What are the functions of the male accessory sex glands?

The accessory sex glands secrete materials that support gametes.

Why is the anterior portion of the perineum called the urogenital triangle?

The anterior portion of the perineum is called the urogenital triangle because its borders form a triangle that encloses the urethral (uro-) and vaginal (-genital) orifices.

How is the bilaminar embryonic disc connected to the trophoblast?

The bilaminar embryonic disc is attached to the trophoblast by the connecting stalk.

How does the blastocyst merge with and burrow into the endometrium?

The blastocyst secretes digestive enzymes that eat away the endometrial lining at the site of implantation.

The ability of a male to ejaculate is due to the action of ________.

The bulbospongiosus muscle

Which structure in males is homologous to the greater vestibular glands?

The bulbourethral glands are homologous to the greater vestibular glands.

What are all chromosomes other than sex chromosomes called?

The chromosomes that are not sex chromosomes are called autosomes.

What hormones are secreted by the corpus luteum?

The corpus luteum secretes progesterone, estrogens, relaxin, and inhibin.

Which muscles help regulate the temperature of the testes?

The cremaster and dartos muscles help regulate the temperature of the testes.

Which part of the decidua helps form the maternal part of the placenta?

The decidua basalis helps form the maternal part of the placenta.

What are the functions of the male ducts?

The ducts transport, store, and receive gametes.

What is the effect of rising but still moderate levels of estrogens on the secretion of GnRH, LH, and FSH?

The effect of rising but moderate levels of estrogens is negative feedback inhibition of secretion of GnRH, LH, and FSH.

What will occur after ovulation?

The endometrium enters its secretory phase.

What structural features of the endometrium contribute to its function?

The endometrium is a highly vascularized, secretory epithelium that provides the oxygen and nutrients needed to sustain a fertilized egg.

What are the two sex chromosomes in females and males?

The female sex chromosomes are XX, and the male sex chromosomes are XY.

Which structure in males is homologous to the clitoris?

The glans penis is homologous to the clitoris.

What are the functions of the gonads (testes)?

The gonads (testes) produce gametes (sperm) and hormones.

What are the groups of reproductive organs in males?

The gonads (testes), ducts, accessory sex glands, and the penis.

Which hormone is responsible for growth of the corpus luteum?

The hormone responsible for growth of the corpus luteum is LH.

Which hormone is responsible for ovulation?

The hormone responsible for ovulation is LH.

Which hormones are responsible for the prolierative phase of endometrial growth?

The hormones responsible for the proliferative phase of endometrial growth are estrogens.

Which hormones are responsible for the surge of LH at midcycle?

The hormones responsible for the surge of LH at midcyle are LH and estrogens.

When declining levels of estrogens and progesterone stimulate secretion of GnRH, is this a positive or a negative feedback effect? Why?

The is negative feedback, because the response is opposite to the stimulus. A reduced amount of negative feedback due to declining levels of estrogens and progesterone stimulates release of GnRH, which in turn increases the production and release of FSH and LH, ultimately stimulating the secretion of estrogens.

To which structure does the mesovarium anchor the ovary?

The mesovarium anchors the ovary to the broad ligament of the uterus and the uterine tube.

What is the function of the midpiece of a sperm cell?

The midpiece contains mitochondria for ATP production for locomotion and metabolism.

What structural features of the myometrium contribute to its function?

The myometrium is a thick smooth muscle layer that supports the uterine wall during pregnancy and contracts to expel the fetus at birth.

What is the function of the neck of a sperm cell?

The neck contains centrioles that produce microtubules for the rest of the tail.

Which structures develop from the neural tube?

The neural tube forms the brain and spinal cord.

What is the significance of the notochord?

The notochord induces mesodermal cells to develop into vertebral bodies and forms the nucleus pulposus of intervertebral discs.

If parents have the genotypes Pp and Pp, what is the chance that their first child will have PKU? What is the chance of PKU occurring in their second child?

The odds that a child will have PKU are the same for each child - 25%.

To which structure does the ovarian ligament anchor the ovary?

The ovarian ligament anchors it to the uterus.

What are the functions of the penis?

The penis assists in the delivery and joining of gametes.

What is the function of the placenta?

The placenta participates in the exchange of materials between fetus and mother, serves as a protective barrier against many microbes, and stores nutrients.

Which hormone is responsible for the differentiation of the external genitals?

The presence of dihydrotestosterone (DHT) stimulates differentiation of the external genitals in males; its absence allows differentiation of the external genitals in females.

What is the function of the principal and end pieces of the tail of a sperm cell?

The principal and end pieces of the tail provide motility.

Of the several estrogens, which one exerts the major effect?

The principal estrogen is beta-estradiol.

Which structure in males is homologous to the paraurethral glands?

The prostate is homologous to the paraurethral glands.

What accessory sex gland constitutes the majority of the seminal fluid?

The seminal vesicles are the accessory sex glands that contribute the largest volume to seminal fluid.

Why doesn't semen enter the urinary bladder during ejaculation?

The smooth muscle sphincter at the base of the urinary bladder closes.

What are the functions of the sperm head?

The sperm head contains the nucleus with 23 highly condensed chromosomes and an acrosome that contains enzymes for penetration of a secondary oocyte.

What is the functional significance of the stratum basalis of the endometrium?

The stratum basalis of the endometrium provides cells to replace those that are shed (the stratum functionalis) during each menstruation.

To which structure does the suspensory ligament anchor the ovary?

The suspensory ligament anchors it to the pelvic wall.

Which structure in males is homologous to the ovaries?

The testes are homologous to the ovaries.

Why do the corpora cavernosa penis and the corpus spongiosum penis become rigid during sexual arousal?

The trapped blood engorges and stiffens the tissue, producing an erection. The corpus spongiosum penis keeps the spongy urethra open so that ejaculation can occur.

What tissue layers cover and protect the testes?

The tunica vaginalis and tunica albuginea are tissue layers that cover and protect the testes.

The dartos and cremaster muscles are important to the integrity of the male reproductive system. What role do they play?

They regulate the temperature of the testes.

It is impossible for sperm to be functional (able to fertilize the egg) until after ________.

They undergo capacitation

This is the part of the blastocyst that promotes implantation and produces hCG.

Trophoblast

This is the part of the blastocyst that promotes implantation and produces hCG. A) Blastocyte B) Blastosphere C) Trophoblast D) Blastocyst cavity E) Uterine cavity

Trophoblast

True or False: Alleles may code for alternative expressions of a genetic trait.

True

True or False: Both tetrads and crossovers are seen during meiosis.

True

True or False: Derivatives of the endoderm include epithelium of the respiratory tract

True

True or False: Failure to attain erection is called impotence.

True

True or False: Freshly deposited sperm are not capable of penetrating an oocyte.

True

True or False: Hemophilia is an X-linked condition caused by a recessive gene.

True

True or False: Of the three germ layers, the mesoderm forms the most body parts.

True

True or False: Sex is readily detected from the genitals during weeks 9-12.

True

True or False: Sexually transmitted infections are the most important cause of reproductive disorders.

True

True or False: Some segments of the Y chromosome have no counterpart on the X chromosome.

True

True or False: The ABO blood group is an example of multiple-allele inheritance

True

True or False: The secretions of the bulbourethral glands neutralize traces of acidic urine in the urethra and serve as a lubricant during sexual intercourse.

True

True or False: The soft mucosal lining of the uterus is the endometrium.

True

True or False: The umbilical vein becomes the ligamentum teres.

True

True or False: When a couple is having difficulty conceiving a child, it is necessary to investigate the sperm of the male.

True

Which condition is a sex chromosome aneuploidy, caused by the presence of a single X chromosome designated XO?

Turner's Syndrome

If gametes were diploid like somatic cells, how many chromosomes would the zygote contain?

Twice the diploid number, and with every succeeding generation, the chromosome number would continue to double and normal development could not occur.

Which tissue masses form the erectile tissue in the penis?

Two tissue masses called the corpora cavernosa penis and one corpus spongiosum penis contain blood sinuses that fill with blood that cannot flow out of the penis as quickly as it flows in.

This is the connection between the placenta and the embryo.

Umbilical Cord

This is the connection between the placenta and the embryo. A) Amnion B) Chorion C) Umbilical cord D) Placenta E) Capillary beds

Umbilical cord

This is the site of fertilization.

Uterine Tubes

This is the site of fertilization. A) Ureters B) Urethra C) Uterine tubes D) Ovaries E) Vagina

Uterine tubes

The umbilical arteries carry ________.

Waste products to the placenta

Involution is what?

When the uterus decreases in size.

Male reproductive system arises from

Wolffian Ducts

The fusion of the male pronucleus and the female pronucleus results in which developmental stage?

Zygote

The fusion of the male pronucleus and the female pronucleus results in which developmental stage? A) Female pronucleus B) Male pronucleus C) Zygote D) Blastomeres E) Morula

Zygote

The morula A) is a hollow ball of cells. B) enters the uterus on day 3 or 4. C) becomes a blastocyst. D) consists of only 8 cells. E) is nourished by fluids in the uterine tube.

becomes a blastocyst

Uterine contractions during labor are stimulated by a positive feedback loop involving a pituitary hormone called A) vasopressin. B) oxytocin. C) prolactin. D) relaxin. E) estrogen.

oxytocin

nourish sperm cells; secrete inhibin A) epididymis B) interstitial (Leydig) cells C) rete testis D) seminiferous tubules E) sustentacular (Sertoli) cells

sustentacular (Sertoli) cells

Involution is A) when the placenta is expelled B) when the umbilical cord is cut C) when the uterus decreases in size D) when the cervix dilates E) None of the above

when the uterus decreases in size