Question 1

Joe and Jane desperately want to have children, and although they have tried for two years, they have not been successful. Finally, they both agree to consult a specialist, and it turns out that Joe suffers from oligospermia (a low sperm count). He doesn't understand why this would interfere with his ability to have children since he remembers from biology class that "it only takes one sperm to fertilize an egg." What should the specialist tell him?

Accepted Answer

Although what Joe says is technically tr...

Question 2

In simple inheritance,

Accepted Answer

A)  phenotypic characteristics are determined by a single pair of alleles.
B)  phenotypic characteristics are determined by multiple alleles.
C)  phenotypic characteristics are determined by the action of two genes.
D)  phenotypic characteristics are controlled by regulator genes on a chromosome other than the one that has the structural genes.
E)  phenotypic characteristics are determined by the genes on the Y chromosome.F) C) and D)
G) A) and B)

Question 3

Regarding Fragile-X syndrome,

Accepted Answer

A)  the affected females have nonfunctional ovaries, and estrogen production occurs at negligible levels.
B)  the cause is trisomy, a mistake that occurs in meiosis, and affected individuals carry an extra chromosome.
C)  the phenotype is male, but the testes fail to mature so the individuals are sterile, and the breasts are slightly enlarged.
D)  the cause is a kind of chromosomal deletion known as monosomy where the phenotype is normal female.
E)  the affected individuals display mental retardation, abnormal facial development, and enlarged testes in affected males.F) B) and E)
G) C) and E)

Question 4

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

Accepted Answer

A)  blastocoele
B)  blastocyst
C)  trophoblast
D)  developing villi
E)  chorionF) B) and C)
G) C) and D)

Question 5

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

Accepted Answer

A)  amnion
B)  placenta
C)  allantois
D)  yolk sac
E)  chorionF) B) and C)
G) C) and E)

Question 6

If an X-carrying sperm fertilizes an egg, the resulting zygote will be

Accepted Answer

A)  either male or female.
B)  male only.
C)  female only.
D)  nonviable.
E)  both male and female.F) A) and C)
G) B) and E)

Question 7

Genes that appear on the X chromosome are said to be

Accepted Answer

A)  X-linked.
B)  autosomal recessive.
C)  heterozygous.
D)  homologous.
E)  lethal.F) A) and C)
G) A) and B)

Question 8

A blastocyst is

Accepted Answer

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.F) A) and E)
G) A) and B)

Question 9

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

Accepted Answer

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

Question 10

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

Accepted Answer

A)  placenta
B)  yolk sac
C)  amnion
D)  allantois
E)  chorionF) A) and E)
G) B) and E)

Question 11

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

Accepted Answer

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.F) A) and D)
G) B) and C)

Question 12

The goal of labor is

Accepted Answer

A)  parturition.
B)  fertilization.
C)  gastrulation.
D)  cleavage.
E)  placentation.F) B) and D)
G) None of the above

Question 13

In which of the following does the individual carry the sex chromosome pattern XXY and is a male?

Accepted Answer

A)  Down's syndrome
B)  Klinefelter's syndrome
C)  Fragile-X syndrome
D)  Trisomy 21
E)  Turner's syndromeF) All of the above
G) B) and E)

Question 14

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

Accepted Answer

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.F) C) and E)
G) C) and D)

Question 15

"Induced" abortions

Accepted Answer

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.F) A) and B)
G) A) and C)

Question 16

Hemophilia is a(n)

Accepted Answer

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

Question 17

Which of the following is a recessive trait?

Accepted Answer

A)  red hair
B)  color blindness
C)  eye color
D)  hemoglobin molecular structure
E)  heightF) C) and D)
G) B) and E)

Question 18

The normal pair of sex chromosomes in males is

Accepted Answer

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

Question 19

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

Accepted Answer

A)  syncytial trophoblast
B)  developing villi
C)  lacuna
D)  uterine gland
E)  amniotic cavityF) C) and E)
G) A) and B)

Question 20

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

Accepted Answer

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 stageF) B) and C)
G) A) and E)

Exam 20: Development and Inheritance

In which of the following does the individual carry the sex chromosome pattern XXY and is a male?

Correct Answer
verified

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

Correct Answer
verified

"Induced" abortions

Correct Answer
verified

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

Correct Answer
verified

If an X-carrying sperm fertilizes an egg, the resulting zygote will be

Correct Answer
verified

Genes that appear on the X chromosome are said to be

Correct Answer
verified

Correct Answer
verified
Although what Joe says is technically tr...
View Answer

The normal pair of sex chromosomes in males is

Correct Answer
verified

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

Correct Answer
verified

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

Correct Answer
verified

Which of the following is a recessive trait?

Correct Answer
verified

The goal of labor is

Correct Answer
verified

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

Correct Answer
verified

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

Correct Answer
verified

A blastocyst is

Correct Answer
verified

Regarding Fragile-X syndrome,

Correct Answer
verified

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

Correct Answer
verified

In simple inheritance,

Correct Answer
verified

Hemophilia is a(n)

Correct Answer
verified

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

Correct Answer
verified

Exam 20: Development and Inheritance

In which of the following does the individual carry the sex chromosome pattern XXY and is a male?

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

"Induced" abortions

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

If an X-carrying sperm fertilizes an egg, the resulting zygote will be

Correct AnswerverifiedShow Answer

Genes that appear on the X chromosome are said to be

Correct AnswerverifiedShow Answer

Correct AnswerverifiedAlthough what Joe says is technically tr...View AnswerShow Answer

The normal pair of sex chromosomes in males is

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Which of the following is a recessive trait?

Correct AnswerverifiedShow Answer

The goal of labor is

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

A blastocyst is

Correct AnswerverifiedShow Answer

Regarding Fragile-X syndrome,

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

In simple inheritance,

Correct AnswerverifiedShow Answer

Hemophilia is a(n)

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
verified
Although what Joe says is technically tr...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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