chapter 3

Meko has dark hair and dark eyes, even though his biological mother is fair-skinned. Meko's hair and eye color are part of his

phenotype

Where does the fertilization of the ovum take place in a normal pregnancy?

Fallopian tubes

A normally developing fetus has reached a length of 12 inches and weighs about one pound. Using ultrasound, it is possible to tell if the fetus is male or female. In which stage of development is this fetus?

Fetal

The embryonic stage of gestation covers what time period?

First 2-8 weeks

What is the term used to describe cells that unite at conception?

Gametes

Which of these genetic disorders usually does not express symptoms until adulthood?

Huntington's disease

What percent of congenital disorders result from harmful genes or faulty chromosomes?

30%

Which of the following best defines genomic imprinting?

A chemical label that identifies whether a gene came from one's father or mother

My father has type A blood and my mother has type O blood. What will my blood type be?

A or O

Phenylketonuria is an example of which of the following?

A recessive autosomal disorder

How are newborn infants affected by medications given to the mother during the birthing process?

Infants whose mothers received analgesics or anesthetics during labor are usually more sluggish, spend more time sleeping, and gain a little less weight during the first weeks after birth.

Your friend is taking Accutane for her adult acne. She comes to you and says that she thinks she is pregnant. What is the best advice that you can give her?

It is best to see her doctor as soon as possible to determine whether or not the drug is safe.

Which of the following is the most common sex-chromosome anomaly?

Klinefelter's syndrome

Which of the following is typical for individuals who have sex chromosome anomalies?

Learning difficulties

Which of the following is the best example of the expressivity of genes?

Linda received a dominant gene for freckles from her father, but Linda's freckles are smaller, lighter, and more widely scattered than those of her father.

When does a developing infant begin to respond to sound?

13-16 weeks

Lorna notices that her fetus has begun to kick and move. Her physician tells her that she can hear a heartbeat with a stethoscope. Lorna is most likely at what point in her pregnancy?

17-20 weeks

Which of the following is a correct statement about the events leading up to conception?

After ejaculation, sperm travel the following path: the woman's vagina, cervix, uterus, and fallopian tube.

Not long after Gloria found out she was pregnant, she began having pain. When she went to her doctor, she was told that the zygote had implanted in her fallopian tube rather than in her uterus. What type of pregnancy is this?

An ectopic pregnancy

Mrs. Lincoln is receiving information and advice about prenatal care from her health care team. With regard to alcohol, what advice will they most likely give Mrs. Lincoln?

Avoid alcohol entirely.

Synapses are formed following the development of which of the following neural structures?

Axons and dendrites

Skylar has brown eyes, thin lips, and curly brown hair. Which of these traits is polygenic?

Brown eyes

Gina appeared to be a healthy pregnant woman but her baby was born with central nervous system damage, and later it was determined that the child was completely deaf and has mental retardation. Which of the following would be the most likely cause?

Cytomegalovirus

Which of the following is the final stage of labor?

Delivery of the placenta

Which stage begins when implantation is complete and continues through organogenesis?

Embryonic stage

Recent research has found that diseases that appear as we age may be a result of which of the following?

Genomic imprinting

Which of the following terms describes an individual's unique genetic blueprint, which is created from genes contributed by both parents?

Genotype

A blastocyst is floating inside of Daria's uterus. In what stage is Daria's pregnancy?

Germinal

Which of the following correctly lists the stages of prenatal development in order of progression?

Germinal, embryonic, fetal

Which of the following is a condition that can cause a baby to grow too rapidly and result in premature labor or an infant that is too large for a vaginal birth?

Gestational diabetes

Which of the following serve to hold neurons together?

Glial cells

Of the following, which is a true statement about the influence of heroin and methadone upon prenatal and infant development?

Heroin or methadone use can cause miscarriage, premature labor, and death of the infant.

Chromosomes are composed of which of the following?

Molecules of deoxyribonucleic acid

What is the difference between gametes and all other body cells?

Most cells in the human body contain 23 pairs of chromosomes. Gametes are sperm and ovum cells that have only 23 unpaired chromosomes.

Which of the following is associated with the second trimester of pregnancy?

Movements of the fetus

Which of the following individuals has the greatest risk for bearing a child with trisomy 21?

Mrs. Black, age 45

Which of the following terms describes physical traits that are influenced by both genes and the environment?

Multifactorial

Janae and Sean are siblings who come from a family with a history of anxiety. Janae is somewhat anxious but generally takes things in stride. Sean, however, is always concerned about his health, his job, and his family even when there is no reason. Which of the following concepts best explains the difference between Janae and Sean?

Multifactorial inheritance

Samson is taller and has a higher IQ than either of his parents. Which of the following terms would be used to explain this?

Multifactorial inheritance

What is the term for the pattern of inheritance in which many genes influence a trait?

Polygenic inheritance

Most sex-linked disorders are caused by which of the following?

Recessive genes

Which of the following statements is true regarding prenatal sex differentiation?

Sex differentiation begins at around 4 to 8 weeks of gestation

Which of the following aspects of neonatal functioning is assessed by the Apgar scale?

Skin color

Which of the following is a conclusion drawn from The Cat in the Hat studies?

That newborn infants respond to sounds that they heard during the last trimester of development

Which of the following is a characteristic of a child born with fetal alcohol spectrum disorder?

The child may be mentally retarded

Which of the following is associated with maternal malnutrition?

The development of mental illnesses in adulthood

Which of the following best summarizes our understanding of the effects of maternal cocaine use on fetuses and infants?

The effects are not clearly understood because it is difficult to separate the effects of cocaine from those of poverty and other drugs.

Carmelita has smoked an average of one pack of cigarettes per day throughout her pregnancy. How is this likely to affect her fetus?

The infant may weigh less than normal at birth.

Which of the following is formed from cells from the outer layer of the blastocyst and the uterine wall?

The placenta

Which of the following best describes neuronal proliferation?

The rapid increase in the formation of neurons, which takes place between 10 and 18 weeks of gestation

Which of the following is the best example of the proximodistal pattern of development during the prenatal period?

The spinal cord develops before the arms.

Which of the following is true of identical twin studies?

The study of monozygotic twins is important because it helps us, to some extent, identify genetic versus environmental causes of behavior.

Which of the following is true of a trait controlled by a dominant gene?

The trait will be expressed even if the instructions of the corresponding gene in the other half of the pair are different.

Which of the following happens during the first trimester of pregnancy?

The zygote implants itself in the lining of the uterus.

What is the prognosis for children born with trisomy 13 or 18?

They rarely live past infancy

Salina is becoming emotionally attached to her unborn fetus. Her breasts are secreting colostrum. Salina is most likely in which trimester?

Third

What is a trisomy?

Three copies of a specific autosome

Pregnant women should eat foods high in folic acid, such as beans or spinach, during pregnancy. What is the purpose of this dietary recommendation?

To reduce the risk of neural tube defects such as spina bifida

Which of the following is true regarding prenatal infection with HIV?

Transmission is more likely when the mother has AIDS rather than HIV.

Reese is anatomically female, but did not develop breasts or menstruate at puberty and needed hormone therapy. With which of the following was Reese most likely born?

Turner's syndrome

Nadia is exposed to high levels of radiation during the 6th, 7th, and 8th weeks of gestation. Which of the following organ structures in the fetus are most likely to show abnormalities?

Virtually all organ systems are vulnerable during this time.

Under what circumstance(s) will a recessive gene be expressed?

When it is paired with another recessive gene for the same trait

At what point does the fetal period begin?

When the process of organogenesis is complete

The genes that cause sex-linked disorders are found on the

X chromosome.

Which of the following is a commonly used prenatal diagnostic procedure?

alpha-fetoprotein screening

Phillip has red hair, which comes from a recessive gene. This must mean that Phillip received the gene from

both parents.

When researchers have examined the relationship between maternal emotions and prenatal development, the most consistent finding has been that

fetuses of severely distressed mothers tend to grow more slowly.

Which of the following is true of a trait that is passed through mitochondrial inheritance?

it is passed from a mother to her children.

Organogenesis is

the process by which the basic structures of the embryo's organs, organ systems, and body parts are completed.