Deck 20: Development and Inheritance

Question 1

Polyspermy is

A) when fertilization involves more than one sperm.
B) when multiple sperm release hyaluronidase concurrently.
C) the movement of millions of sperm through the female reproductive tract.
D) the clinical term for an adequate sperm count (more than 20 million per ejaculate).
E) the process that follows capacitation and enables sperm to bind to sperm receptors.

Answer 1

A

Question 2

The extraembryonic membrane that contains fluid that surrounds and cushions the developing embryo and fetus is known as the

A) yolk sac.
B) amnion.
C) allantois.
D) chorion.
E) uterus.

Answer 2

B

Question 3

The division of the zygote into two blastomeres occurs during

A) cleavage.
B) implantation.
C) placentation.
D) embryogenesis.
E) fertilization.

Answer 3

A

Question 4

Which of the following forms when blood vessels form in the chorion,around the periphery of the blastocyst?

A) allantois
B) placenta
C) blastocoele
D) amnion
E) trophoblast

Question 5

Differentiation is

A) the transfer of genetic information from one generation to the next.
B) the gradual change in anatomical and physiological characteristics from conception to maturity.
C) the formation of more specialized cell types through selective changes in genetic activity.
D) the fusion of two haploid gametes that results in one diploid zygote.
E) a developmental stage of the embryo where body shape becomes discernable.

Question 6

The period of gestation that is characterized by rapid fetal growth and adipose tissue deposition is the ________ trimester(s).

A) first
B) second
C) third
D) first and second
E) second and third

Question 7

Choose the correct statement about amphimixis.

A) a process that results in a zygote
B) a genetic disorder based on autosomal dominance
C) the transition from morula to blastocyst
D) the time during which sperm travel toward the ovum
E) the formation of the male and female pronuclei

Question 8

The extraembryonic membrane that forms the urinary bladder is the

A) placenta.
B) allantois.
C) amnion.
D) chorion.
E) yolk sac.

Question 9

The period of gestation when the basic components of each of the major organ systems appear is the ________ trimester(s).

A) first
B) second
C) third
D) first and second
E) second and third

Question 10

The morula stage occurs during which process?

A) embryogenesis
B) placentation
C) gastrulation
D) implantation
E) cleavage

Question 11

The yolk stalk and body stalk fuse during week five,forming the

A) amnion.
B) allantois.
C) chorion.
D) umbilical stalk.
E) primitive streak.

Question 12

Fertilization of the ovum usually occurs

A) within one hour of ovulation.
B) as much as three to four days following ovulation.
C) in the ovary.
D) in the upper third of the uterine tube.
E) in the uterus.

Question 13

The first extraembryonic membrane to appear is the

A) chorion.
B) allantois.
C) placenta.
D) yolk sac.
E) amnion.

Question 14

A blastocyst is

A) an extraembryonic membrane that forms blood vessels.
B) a solid ball of cells.
C) a hollow ball of cells.
D) a portion of the placenta.
E) the membrane that forms the urinary bladder.

Question 15

The outer layer of cells separating the outside world from the blastocoele is called the

A) trophoblast.
B) chorion.
C) inner cell mass.
D) zona pellucida.
E) blastomere.

Question 16

Gastrulation produces an oval,three-layered sheet known as the

A) chorion.
B) blastula.
C) embryonic disc.
D) morula.
E) blastocyst.

Question 17

The study of the development of the human organism during the first two months after fertilization is called

A) genetics.
B) embryology.
C) pediatrics.
D) anthropology.
E) gerontology.

Question 18

The ectoderm forms which of the following?

A) muscle
B) all lymphatic structures
C) the cardiovascular system
D) the thymus, thyroid gland, and pancreas
E) all neural tissues

Question 19

The mesoderm forms (the)

A) muscle.
B) epidermis.
C) neural tissues.
D) mucous epithelium of nasal passageways.
E) pituitary gland and adrenal medullae.

Question 20

The hollow cavity within the blastocyst is the

A) gastrula.
B) morula.
C) blastocoele.
D) yolk sac.
E) amnion.

Question 21

Figure 20-1 Events in Implantation
Use Figure 20-1 to identify the labeled part.
Label C represents which of the following structures?

A) blastocoele
B) blastocyst
C) trophoblast
D) developing villi
E) chorion

Question 22

Which extraembryonic structure is created as migrating mesodermal cells form a layer beneath the trophoblast,separating it from the blastocoele?

A) amnion
B) placenta
C) allantois
D) yolk sac
E) chorion

Question 23

The presence of ________ in blood or urine is a reliable indication of pregnancy.

A) estrogen and progesterone
B) luteinizing hormone
C) human placental lactogen
D) human chorionic gonadotropin
E) relaxin

Question 24

Near the end of the first trimester,deoxygenated blood flows from the developing embryo or fetus to the placenta through

A) paired umbilical veins.
B) the superior vena cava.
C) one umbilical vein.
D) three umbilical arteries.
E) paired umbilical arteries.

Question 25

Figure 20-1 Events in Implantation
Use Figure 20-1 to identify the labeled part.
Label A represents which of the following structures?

A) syncytial trophoblast
B) developing villi
C) lacuna
D) uterine glands
E) amniotic cavity

Question 26

Which process begins as the surface of the blastocyst next to the inner cell mass adheres to the uterine lining?

A) oocyte activation
B) placentation
C) embryogenesis
D) implantation
E) blastocyst formation

Question 27

Figure 20-1 Events in Implantation
Use Figure 20-1 to identify the labeled part.
Label F represents which of the following structures?

A) blastocyst
B) inner cell mass
C) trophoblast
D) syncytial trophoblast
E) cellular trophoblast

Question 28

During implantation,

A) the syncytial trophoblast erodes a path through the uterine epithelium.
B) the inner cell mass begins to form the placenta.
C) maternal blood vessels in the endometrium are walled off from the blastocyst.
D) the entire trophoblast becomes syncytial.
E) the inner cell mass is temporarily deprived of nutrients.

Question 29

If the gonads fail to develop very early during human development,the contributions of which germ layer may be deficient?

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

Question 30

Which extraembryonic membrane is an important site of blood cell production?

A) placenta
B) yolk sac
C) amnion
D) allantois
E) chorion

Question 31

Figure 20-1 Events in Implantation
Use Figure 20-1 to identify the labeled part.
Label E represents which of the following structures?

A) blastocyst
B) inner cell mass
C) trophoblast
D) syncytial trophoblast
E) cellular trophoblast

Question 32

The conversion of mammary glands from resting to active states requires the presence of both placental hormones and

A) oxytocin and insulin.
B) progesterones and estrogens.
C) human chorionic gonadotropin and parathyroid hormones.
D) glucagon and somatostatin.
E) growth hormones, prolactin, and thyroid hormones.

Question 33

Separation of the inner cell mass from the trophoblast forms the

A) blastocoele.
B) lacunae.
C) amniotic cavity.
D) chorion.
E) allantois.

Question 34

Figure 20-1 Events in Implantation
Use Figure 20-1 to identify the labeled part.
Label D represents which of the following structures?

A) blastocoele
B) blastocyst
C) trophoblast
D) developing villi
E) chorion

Question 35

Figure 20-1 Events in Implantation
Use Figure 20-1 to identify the labeled part.
Label G represents which of the following structures?

A) syncytial trophoblast
B) developing villi
C) lacuna
D) uterine gland
E) amniotic cavity

Question 36

Which statement regarding placental circulation is true?

A) Oxygenated maternal blood re-enters the mother's venous system through chorionic villi.
B) Maternal and fetal blood mix near the placenta.
C) Deoxygenated maternal blood re-enters the mother's venous system through small uterine veins.
D) Deoxygenated blood leaves the chorionic villi through umbilical arteries.
E) Oxygenated fetal blood enters the chorionic villi through umbilical arteries.

Question 37

Which of the following is a hormone secreted by both the placenta and the corpus luteum during pregnancy and functions in suppressing the release of oxytocin?

A) progesterone
B) human chorionic gonadotropin
C) relaxin
D) placental prolactin
E) estrogen

Question 38

The chorionic villi

A) help prepare the mammary glands for milk production.
B) are free endodermal tips that grow toward the wall of the blastocyst.
C) bulge into the amniotic cavity at the head fold and extend toward the trophoblast.
D) provide the surface area for gaseous exchange between fetal and maternal bloodstreams.
E) form constrictions that narrow the yolk stalk and the body stalk between the embryo and the surrounding trophoblast.

Question 39

Figure 20-1 Events in Implantation
Use Figure 20-1 to identify the labeled part.
Label B represents which of the following structures?

A) blastocoele
B) blastocyst
C) trophoblast
D) developing villi
E) chorion

Question 40

Which of the following results from endodermal contributions?

A) all cardiovascular components
B) brain and spinal cord
C) dermis and hypodermis
D) stem cells that produce gametes
E) nephrons

Question 41

The aging process is called

A) neonate stage.
B) puberty.
C) senescence.
D) adolescence.
E) weaning.

Question 42

The goal of labor is

A) parturition.
B) fertilization.
C) gastrulation.
D) cleavage.
E) placentation.

Question 43

During pregnancy,

A) maternal respiratory rate decreases.
B) maternal blood volume decreases.
C) maternal nutrient requirements decrease significantly.
D) a woman's glomerular filtration rate decreases by 20 percent.
E) maternal tidal volume increases.

Question 44

When two separate oocytes are ovulated and fertilized,________ develop.

A) identical twins
B) conjoined twins
C) monozygotic twins
D) polygametic twins
E) dizygotic twins

Question 45

The last stage of labor is the

A) dilation stage.
B) expulsion stage.
C) placental stage.
D) decidual stage.
E) neonate stage.

Question 46

Neural tube formation occurs during which gestational age?

A) 4 months
B) 2 weeks
C) 1 month
D) 9 weeks
E) 5 months

Question 47

Figure 20-1 Events in Implantation
Use Figure 20-1 to identify the labeled part.
Label I represents which of the following structures?

A) syncytial trophoblast
B) developing villi
C) lacuna
D) uterine gland
E) amniotic cavity

Question 48

Which of the following is an example of positive feedback during labor?

A) the movement of the fetus toward the cervical canal
B) the pressure the unborn exerts on the cervix
C) the distortion of the myometrium stimulates oxytocin release
D) the dilation of the cervix followed by the rupture of the amnion
E) the ejection of the placenta at the end of the placental stage

Question 49

Regarding lactation and the mammary glands,which statement is true?

A) Colostrum contains more proteins than breast milk.
B) An expectant mother's mammary glands begin producing colostrum by the end of the second month of pregnancy.
C) As colostrum production increases, the mammary glands convert to milk production.
D) Colostrum, unlike milk, contains large quantities of lysozymes.
E) Colostrum has much more fat than breast milk.

Question 50

Regarding the growth spurt in girls in the United States,the growth rate is maximal between the ages of

A) 5-9 years.
B) 9-11 years.
C) 10-13 years.
D) 14-15 years.
E) 16-18 years.

Question 51

"Induced" abortions

A) happen due to physiological problems.
B) are called "miscarriages."
C) are performed when continuing a pregnancy represents a threat to the life and health of the mother.
D) occur due to developmental problems.
E) are performed at the woman's request.

Question 52

Match the gestational age with the corresponding prenatal development.

A) 1 month / mammary glands develop
B) 2 months / movement of fetus can be felt by mother
C) 3 months / formation of the gonads, ducts, and genitalia
D) 4 months / eye and ear formation
E) 5 months / migration of lymphocytes to lymphoid organs

Question 53

Figure 20-1 Events in Implantation
Use Figure 20-1 to identify the labeled part.
Label H represents which of the following structures?

A) blastocyst
B) inner cell mass
C) trophoblast
D) blastocoel
E) lacuna

Question 54

The stage of labor during which the fetus begins to shift toward the cervical canal is the

A) emergence stage.
B) dilation stage.
C) placental stage.
D) expulsion stage.
E) fetal stage.

Question 55

When labor begins,the fetal pituitary gland secretes ________,which may be the actual trigger for the onset of labor.

A) prolactin
B) hCG
C) oxytocin
D) growth hormone
E) thyroxine

Question 56

Figure 20-1 Events in Implantation
Use Figure 20-1 to identify the labeled part.
Label J represents which of the following structures?

A) syncytial trophoblast
B) developing villi
C) lacuna
D) uterine gland
E) amniotic cavity

Question 57

Which statement is true regarding conjoined twins?

A) Splitting of the inner cell mass may have occurred before gastrulation.
B) Surgical separation is nearly impossible even with minor fusion.
C) Separation of the blastomeres early in cleavage may have occurred.
D) Splitting of the blastomeres or of the embryonic disc is not complete.
E) Two separate oocytes are fertilized at the same time.

Question 58

Figure 20-1 Events in Implantation
Use Figure 20-1 to identify the labeled part.
Label K represents which of the following structures?

A) blastocoele
B) blastocyst
C) trophoblast
D) developing villi
E) chorion

Question 59

At which gestational age do basic heart structures,major blood vessels,lymph nodes,and ducts form?

A) month 6
B) month 8
C) month 4
D) month 7
E) month 2

Question 60

Distortion of the cervix stimulates maternal release of which hormone?

A) estrogen
B) progesterone
C) oxytocin
D) relaxin
E) human chorionic gonadotropin

Question 61

Hemophilia is a(n)

A) example of dominance.
B) example of codominance.
C) polygenic trait.
D) recessive trait.
E) sex-linked trait.

Question 62

If an individual carries two different alleles of the same gene,he or she is ________ for the trait determined by that gene.

A) homologous
B) homozygous
C) heterozygous
D) autosomal
E) polygenic

Question 63

Which of the following is a major hormonal event at the onset of puberty?

A) The hypothalamus decreases its production of GnRH.
B) Circulating levels of FSH decrease rapidly.
C) Ovarian cells become less sensitive to FSH.
D) Testicular cells become less sensitive to LH and FSH.
E) Pituitary gland cells become more sensitive to GnRH.

Question 64

The period of sexual and physical maturation is (the)

A) infancy.
B) childhood.
C) senescence.
D) adolescence.
E) neonatal period.

Question 65

The period from birth to the end of the first month is known as (the)

A) senescence.
B) neonatal period.
C) infancy.
D) childhood.
E) embryogenesis.

Question 66

Sperm carry

A) only one X sex chromosome, exclusively.
B) only one Y sex chromosome, exclusively.
C) no sex chromosomes.
D) two Y sex chromosomes.
E) one X or one Y sex chromosome.

Question 67

Which of the following phenotypic characteristics is an example of "codominance"?

A) normal skin pigmentation
B) hair color other than pure blond or red
C) presence of Rh factor on red blood cell membranes
D) presence of A or B antigens on red blood cell membranes
E) ability to taste phenylthiocarbamate (PTC)

Question 68

Human somatic cells contain ________ chromosomes.

A) 24, or 12 pairs of
B) 46, or 23 pairs of
C) 92, or 46 pairs of
D) 12, or 6 pairs of
E) 16, or 8 pairs of

Question 69

The purpose of the Human Genome Project (HGP)is to

A) identify alleles for research in the field of autosomal recessive diseases.
B) describe the full set of genetic material in human chromosomes.
C) discover new methods for fingerprinting and other forensic methods.
D) create a "master race" by limiting the gene pool to carriers of desirable genes.
E) study human development and to ultimately find a way to slow down senescence.

Question 70

Ova carry

A) one X sex chromosome.
B) XX sex chromosomes.
C) YY sex chromosomes.
D) XO sex chromosomes.
E) one Y sex chromosome.

Question 71

The portion of DNA that codes for a particular polypeptide is called a

A) genome.
B) phenotype.
C) karyotype.
D) trait.
E) gene.

Question 72

Choose the correct statement regarding neonates.

A) Urinary water losses are low.
B) The digestive system is extremely active before birth.
C) Neonatal respiratory rates are considerably lower than those of adults.
D) Typical neonatal heart rates are lower than fetal heart rates.
E) At birth, the lungs are fully expanded and filled with fluid.

Question 73

Which of the following is a recessive trait?

A) red hair
B) color blindness
C) eye color
D) hemoglobin molecular structure
E) height

Question 74

Paired chromosomes are called

A) homologous chromosomes.
B) autosomal chromosomes.
C) homozygous chromosomes.
D) heterozygous chromosomes.
E) alleles.

Question 75

A relatively common inherited autosomal recessive disorder is

A) Duchenne muscular dystrophy.
B) cystic fibrosis.
C) Huntington's disease.
D) hemophilia.
E) Marfan's syndrome.

Question 76

Polygenic traits include

A) eye color and hair colors other than pure blond or red.
B) a lack of A and B surface antigens and presence of RH factor.
C) inability to roll the tongue into a U-shape and near-sightedness.
D) photic sneeze reflex and attached earlobes.
E) ability to taste phenylthiocarbamate and color blindness.

Question 77

Which statement regarding the neonatal renal system is true?

A) Neonates can highly concentrate urine prior to excretion.
B) As waste products build up in venous blood, they are excreted at the kidneys.
C) Glomerular filtration does not occur until birth.
D) Glomerular filtration is normal.
E) Neonatal fluid requirements are proportionally much lower than those of adults.

Question 78

An allele that is ________ will be expressed only if it is present on both chromosomes of a homologous pair.

A) dominant
B) recessive
C) incomplete
D) phenotypic
E) autosomal

Question 79

In humans,the 22 pairs of chromosomes,which contain most of the genes that affect somatic characteristics such as hair color and skin pigmentation,are called

A) alleles.
B) heterozygous chromosomes.
C) homologous chromosomes.
D) autosomal chromosomes.
E) homozygous chromosomes.

Question 80

The normal pair of sex chromosomes in males is

A) XX.
B) XO.
C) YO.
D) XY.
E) YY.