Chapter 3 Quick Quiz

1. The one cell that develops when two gametes fuse during fertilization is the beginning of a new person. This one cell is known as a(n)a. ova. c. zygote.b. sperm. d. embryo.

2. David and Daniel are twins who are genetically identical and are known as ___________ twins. Annabelle and Timothy are also twins, but they are obviously ___________ twins.a. monozygotic; identical c. monozygotic; dizygoticb. dizygotic; fraternal d. dizygotic; monozygotic

3. When examining the transmission of phenylketonuria (PKU), a recessive trait, we can clearly identify the ___________ when a child is afflicted with PKU. For the child not afflicted with PKU, we can only identify the ___________, since the child may or may not be a carrier.a. genotype; phenotype c. X-linked genes; Y-linked genesb. phenotype; genotype d. Y-linked genes; X-linked genes

4. If there are two dissimilar chromosomes in the 23rd pair, we can say that this infanta. has Down’s syndrome. c. is a girl.b. will not survive. d. is a boy.

5. The earliest prenatal testing is a first-trimester screening that combines two popular forms of prenatal testing. This test combines which two popular prenatal tests?a. sonogram and amniocentesis c. blood test and sonogramb. embryoscopy and fetal blood sampling d. chorionic villus sampling and blood test

6. Ben’s parents agree that he inherited his intelligence. However, at his college graduation, they discussed how their efforts to encourage his intellectual curiosity by trips to museums and reading increased his intelligence. This suggestion, that the determination of intelligence is by a combination of genetic and environmental factors, is referred to asa. natural selection. c. multifactorial transmission.b. unnatural selection. d. unifactorial transmission.

7. Genetics has been shown to produce a tendency for all of the following psychological disorders EXCEPTa. schizophrenia. c. depression.b. histrionic personality disorder. d. attention deficit-hyperactivity disorder.

8. The three stages of prenatal development occur in the following order:a. fertilization, embryonic, fetal c. fertilization, fetal, neonateb. germinal, embryonic, fetal d. neonate, fetal, germinal

9. The procedure in which fertilization occurs outside the mother’s body is known asa. artificial insemination. c. surrogacy.b. neonate transfer. d. in vitro fertilization.

10. Examples of teratogens that produce birth defects are all of the following EXCEPTa. alcohol. c. pollution.b. German measles. d. milk.

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Chapter 3 Quick Quiz Answers

1. Chapter Section: Earliest DevelopmentAnswer: c Page(s): 54 Type: FactualRationale: When the two gametes fuse and become one cell, that one new cell is known as the zygote.

2. Chapter Section: Earliest DevelopmentAnswer: c Page(s): 55, 56 Type: AppliedRationale: Monozygotic twins are genetically identical (David and Daniel) while dizygotic twins are produced when two separate ova are fertilized by two separate sperm at roughly the same time. Dizygotic twins are only as similar as any other siblings. Since Annabelle and Timothy are not the same sex, we can assume that they must be dizygotic twins.

3. Chapter Section: Earliest DevelopmentAnswer: a Page(s): 57–59 Type: AppliedRationale: This question requires that the student understand the definition of genotype (actual combination of genetic material) and phenotype (the observable trait), as well as the basics of genetic transmission. PKU is an inherited recessive disorder produced by a single allele. Therefore, the child afflicted with PKU must have two recessive genes, the genotype (pp). On the other hand, a child not afflicted with PKU may have either two dominant genes or one dominant and one recessive gene. We can only determine this child’s phenotype (no presence of PKU) not the genotype (Pp or PP).

4. Chapter Section: Earliest DevelopmentAnswer: d Page(s): 56, 57 Type: ConceptualRationale: The 23rd pair of chromosomes is the one that determines the sex of the child. If the child is a girl, she will have two X chromosomes. If the child has one X and one Y, two dissimilar chromosomes (X chromosome is relatively large while the Y chromosome is not), the child is a boy.

5. Chapter Section: Earliest DevelopmentAnswer: c Page(s): 62 Type: FactualRationale: The earliest prenatal test is a first-trimester screening that combines a blood test and ultrasound sonography in the 11th to 13th week of pregnancy.

6. Chapter Section: The Interaction of Heredity and EnvironmentAnswer: c Page(s): 67, 68 Type: ConceptualRationale: Ben’s parents acknowledge the role of both heredity and environment. In this example, the determination of intelligence is by a combination of both genetic and environmental factors. Ben’s parents suggest that his genotype provided a range within which the phenotype may be expressed; this is known as multifactorial transmission.

7. Chapter Section: The Interaction of Heredity and EnvironmentAnswer: b Page(s): 73 Type: ConceptualRationale: Evidence suggests that certain psychological disorders are brought about by genetic factors. Schizophrenia, major depression, alcoholism, autism, and attention deficit-hyperactivity disorder all have significant inherited components.

8. Chapter Section: Prenatal Growth and ChangeAnswer: b Page(s): 76 Type: FactualRationale: There are three prenatal periods. In chronological order, they are germinal (fertilization to 2 weeks), embryonic (2 weeks to 8 weeks) and fetal (8 weeks through birth).

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9. Chapter Section: Prenatal Growth and ChangeAnswer: d Page(s): 79 Type: FactualRationale: In vitro fertilization is a procedure in which a woman’s ova are removed from her ovaries, and a man’s sperm are used to fertilize the ova in a laboratory. Artificial insemination is the process of fertilization in which a man’s sperm is placed directly into the woman’s vagina by a physician.

10. Chapter Section: Prenatal Growth and ChangeAnswer: d Page(s): 81 Type: ConceptualRationale: Teratogens are environmental agents such as drugs, chemicals, viruses, or other factors that produce a birth defect. Alcohol, German measles, and pollution are all potential teratogens.

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Chapter 3The Start of Life: Genetics and Prenatal Development

Multiple Choice Questions

3.1 The sex cells from the mother and father that form a new cell at conception are calleda. gametes. c. DNA.b. chromosomes. d. genes.

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 54 Type: FactualRationale: The sex cells from the mother and father that form a new cell at conception are known as gametes.

3.2 The new cell formed by the process of fertilization is called a(n):a. gamete. c. embryo.b. zygote. d. fetus.

Chapter Section: Earliest DevelopmentAnswer: b Page(s): 54 Type: FactualRationale: The zygote is the new cell formed by the process of fertilization.

3.3 The basic units of genetic information are called:a. gametes. c. deoxyribonucleic acid.b. chromosomes. d. genes.

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 55 Type: FactualRationale: Genes are the basic unit of genetic information.

3.4 ___________, humans receive 70,000 to 100,000 genes, contained on 46 chromosomes.a. During the prenatal period c. At the moment of conceptionb. Upon birth d. During the first two years of life

Chapter Section: Earliest DevelopmentAnswer: c Page(s): 55 Type: FactualRationale: Genes are passed on at the moment of conception.

3.5 Chromosomes are rod-shaped portions of DNA that are organized in ___________ pairs.a. 21 c. 46b. 42 d. 23

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 55 Type: FactualRationale: Chromosomes are rod-shaped portions of DNA that are organized in 23 pairs.

3.6 The substance that genes are composed of that determines the nature of every cell in the body and how it will function is known as ___________.a. DNA c. chromosomesb. RNA d. gametes

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 55 Type: FactualRationale: DNA (deoxyribonucleic acid) is the substance that genes are composed of that determines the nature of every cell in the body and how it will function.

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2 All genes are composed of specific sequences of ___________ molecules.a. DNA c. chromosomesb. RNA d. gametes

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 55 Type: FactualRationale: All genes are composed of specific sequences of DNA.

3.2 The rod-shaped portions of DNA that are organized in 23 pairs are calleda. DNA. c. gametes.b. RNA. d. chromosomes.

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 55 Type: FactualRationale: The genes, composed of specific sequences of DNA, are arranged in specific locations and in a specific order along the 46 chromosomes.

3.3 Each parent provides one of the two ___________ in the 23 pairs that form a new cell at conception.a. DNA c. chromosomesb. RNA d. gametes

Chapter Section: Earliest DevelopmentAnswer: c Page(s): 55 Type: FactualRationale: Each parent provides one of the two chromosomes in each pair of chromosomes that together form the zygote.

3.4 When ___________ (the sex cells, sperm, and ova) are formed in the adult human body, the process is called meiosis.a. DNA c. chromosomesb. RNA d. gametes

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 55 Type: FactualRationale: The gametes are the sex cells from the mother and father that form a new cell at conception. They are formed through the process of meiosis, in which each gamete receives one of the two chromosomes that make up each of the 23 pairs.

3.5 At the moment of conception, the chromosomes obtained from the mother and father unite within a single new cell, called aa. zygote. c. chromosome.b. gamete. d. gene.

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 54, 55 Type: FactualRationale: The zygote, which is the new cell formed by the process of fertilization, is created at conception with the uniting of the chromosomes from the mother and father.

3.6 Twins who are genetically identical are known as ___________ twins.a. dizygotic c. dominantb. monozygotic d. recessive

Chapter Section: Earliest DevelopmentAnswer: b Page(s): 55, 56 Type: FactualRationale: Two genetically identical zygotes, because they come from the same original zygote, are called monozygotic or identical twins. Because they come from the same original zygote, they are genetically identical.

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3 Sharla and Shayla look exactly alike, their mannerisms are similar, they even seem to think alike, and their genes are identical. Sharla and Shayla are ___________ twins.a. dizygotic c. dominantb. monozygotic d. recessive

Chapter Section: Earliest DevelopmentAnswer: b Page(s): 55, 56 Type: ConceptualRationale: Since Sharla and Shayla have identical genes, they must be monozygotic twins. These are twins that are formed from two genetically identical zygotes.

3.2 ___________ twins are genetically identical. Any differences in their development can be attributed only to environmental factors.a. Dizygotic c. Dominantb. Monozygotic d. Recessive

Chapter Section: Earliest DevelopmentAnswer: b Page(s): 55, 56 Type: FactualRationale: Monozygotic twins are genetically identical; therefore, any variation in their development must be attributed to environmental factors. Concerning the nature vs. nurture question, monozygotic twins have an identical nature; therefore, the diversity must be due to nurture.

3.3 Kimberly and Kathy are genetically identical; this means that they are ___________ twins.a. monozygotic c. trizygoticb. dizygotic d. quadzygotic

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 55, 56 Type: ConceptualRationale: Since the girls are genetically identical, they must be monozygotic, from one zygote.

3.4 Twins who are produced when two separate ovaries are fertilized by two separate sperm at roughly the same time are known as ___________ twins.a. dizygotic c. dominantb. monozygotic d. recessive

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 56 Type: FactualRationale: Dizygotic twins are produced when two separate ova are fertilized by two separate sperm at roughly the same time.

3.5 Samantha and Thomas share the exact same birthday and were born to the same mother and father. These twins share many of the same interests yet they are of different genders. Samantha and Thomas are ___________ twins.a. dizygotic c. dominantb. monozygotic d. recessive

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 56 Type: ConceptualRationale: Because the twins are different genders, they are not genetically identical; therefore, they must be dizygotic twins.

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4 Twins produced when a cluster of cells splits off of one ovum within 2 weeks after fertilization are called __________ twins.a. dizygotic c. dominantb. monozygotic d. recessive

Chapter Section: Earliest DevelopmentAnswer: b Page(s): 55–56 Type: FactualRationale: Monozygotic twins are produced when a cluster of cells split off from one ovum, developing into two separate but genetically identical zygotes.

3.2 The one trait that is expressed when two competing traits are present is called the ___________ trait.a. dizygotic c. dominantb. monozygotic d. recessive

Chapter Section: Earliest DevelopmentAnswer: c Page(s): 57 Type: FactualRationale: The one trait that is expressed when two competing traits are present is known as the dominant trait.

3.3 In Mendel’s original pea plant experiment, the offspring plants received genetic information from both the green- and yellow-seeded parents. However, only the color yellow was outwardly expressed in the offspring plants. The color yellow is an example of a ___________ trait.a. dizygotic c. dominantb. monozygotic d. recessive

Chapter Section: Earliest DevelopmentAnswer: c Page(s): 57 Type: ConceptualRationale: The one trait that is expressed when two competing traits are present is known as the dominant trait. In this example, the color yellow is the trait expressed, therefore making it the dominant trait.

3.4 Sara has blond hair and Ishmael has black hair. Their daughter, Susan, received genetic information for hair color from both parents. However, outwardly Susan resembles her father in that they both have black hair. Black hair is an example of a ___________ trait.a. dizygotic c. dominantb. monozygotic d. recessive

Chapter Section: Earliest DevelopmentAnswer: c Page(s): 57 Type: AppliedRationale: The one trait that is expressed when two competing traits are present is known as the dominant trait. In this example, the black hair is the trait expressed, therefore making it the dominant trait.

3.5 In Mendel’s original pea plant experiment, the offspring plants received genetic information from both the green- and yellow-seeded parents. However, only the color yellow was outwardly expressed in the offspring plants. The color green would be considered a ___________ trait.a. dizygotic c. dominantb. monozygotic d. recessive

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 57 Type: ConceptualRationale: The trait within an organism that is present but not expressed is known as the recessive trait. In this example, the color green would be a recessive trait.

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5 Sara has blond hair and Ishmael has black hair. Their daughter, Susan, received genetic information for hair color from both parents. However, outwardly Susan resembles her father in that they both have black hair. The blond hair color would be considered a ___________ trait.a. dizygotic c. dominantb. monozygotic d. recessive

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 57 Type: AppliedRationale: The trait within an organism that is present but not expressed is known as the recessive trait. In this example, the blonde hair would be a recessive trait.

3.2 A trait within an organism that is present but not expressed is called the ___________ trait.a. dizygotic c. dominantb. monozygotic d. recessive

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 57 Type: FactualRationale: The trait within an organism that is present but not expressed is known as the recessive trait.

3.3 The underlying combination of genetic material present (but not outwardly visible) in an organism is known as the organism’s ___________.a. homozygote c. genotypeb. heterozygote d. phenotype

Chapter Section: Earliest DevelopmentAnswer: c Page(s): 57 Type: FactualRationale: The underlying combination of genetic material present in an organism, but not necessarily visible, is known as the genotype.

3.4 The outwardly visible trait that results from an organism’s genetic information is known as the organism’sa. homozygote. c. genotype.b. heterozygote. d. phenotype.

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 57 Type: FactualRationale: The outward, visible trait that is the result of the underlying combination of genetic material present in an organism is known as the phenotype.

3.5 Sasha has blue eyes and Hans has gray eyes. Their son, Antonio, received the genetic information for eye color from both of his parents, even though you cannot determine Antonio’s actual genetic makeup from the color of his eyes. Antonio’s actual genetic information is known as hisa. homozygote. c. genotype.b. heterozygote. d. phenotype.

Chapter Section: Earliest DevelopmentAnswer: c Page(s): 57 Type: ConceptualRationale: The underlying combination of genetic material present in an organism, but not necessarily visible, is known as the genotype. In this example, despite the color of Antonio’s eyes (his phenotype), we do not know the actual genetic information (genotype).

3.6 An observable trait, the trait that can be seen, is known as the organism’s ___________.a. homozygote c. genotypeb. heterozygote d. phenotype

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 57 Type: Factual

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Rationale: An individual’s phenotype is the observable traits, the trait that is actually seen.6 Bita and Behruz have brown eyes. Their son, Kamran, received the genetic information for eye color from

both of his parents and therefore has brown eyes. This outwardly observable genetic trait is known as a person’sa. homozygote. c. genotype.b. heterozygote. d. phenotype.

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 57 Type: ConceptualRationale: An individual’s phenotype is the observable traits, the trait that is actually seen. In this example, Kamran has brown eyes, his phenotype, despite the fact that we don’t know Kamran’s actual genetic information (genotype).

3.2 In Mendel’s original pea plant experiment, the offspring plants received genetic information from both the green- and yellow-seeded parents. However, only the color yellow was outwardly expressed in the offspring plants. The color yellow would be considered the offspring plant’sa. homozygote. c. genotype.b. heterozygote. d. phenotype.

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 57 Type: ConceptualRationale: An individual’s phenotype is the observable traits, the trait that is actually seen. In this example, the color yellow is the phenotype, the observable trait.

3.3 If a child inherits similar genes from each parent, he or she is said to be ___________ for the trait.a. homozygous c. genusb. heterozygous d. phyla

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 57 Type: FactualRationale: Inheriting from parents similar genes for a given trait is referred to as being homozygous for that trait.

3.4 Hannah and Franz both have blond hair and blue eyes. Their daughter, Elsa, has blond hair and blue eyes. Elsa has therefore received similar genes from her parents. She is said to be ___________ for these traits.a. homozygous c. genusb. heterozygous d. phyla

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 57 Type: AppliedRationale: Inheriting from parents similar genes for a given trait is referred to as homozygous for that trait. In this example, both of Elsa’s parents have blond hair and blue eyes. Both blond hair and blue eyes are recessive traits, so this tells us that Elsa’s parents are homozygous, as is Elas herself.

3.5 Sanat and Mohammad both have black hair and brown eyes. Their son Ayman has black hair and brown eyes. It would be necessary to know the underlying combination of genetic material in order to confirm that Ayman has received similar genes from both his parents. If Ayman has received similar genes from both parents, he is said to be ___________ for those traits.a. homozygous c. genusb. heterozygous d. phyla

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 57 Type: AppliedRationale: Inheriting from parents similar genes for a given trait is referred to as homozygous for that trait. In this example, Ayman’s parents both have black hair and brown eyes, dominant traits. Therefore, without knowing their genotype, we cannot be sure of Ayman’s genotype. However, assuming that Ayman has received similar genes from both parents, he would then be considered homozygous for those traits.

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7 If a child inherits different forms of a gene from each parent, he or she is said to be ___________ for the trait.a. homozygous c. genusb. heterozygous d. phyla

Chapter Section: Earliest DevelopmentAnswer: b Page(s): 57 Type: FactualRationale: Inheriting from parents different forms of a gene for a given trait is referred to as heterozygous for that trait.

3.2 Deanna has hazel eyes and Reza has brown eyes. Their son, Bijan, has brown eyes. Bijan has received different forms of a gene from each parent. He is said to be __________ for the trait.a. homozygous c. genotypeb. heterozygous d. phenotype

Chapter Section: Earliest DevelopmentAnswer: b Page(s): 57 Type: ConceptualRationale: Inheriting from parents different forms of a gene for a given trait is referred to as heterozygous for that trait. In this example, Bijan has received a different form of the gene for eye color from each parent. Therefore, he would be heterozygous for that trait.

3.3 Louise has blond hair and Hamid has black hair. Their daughter, Mariam, has black hair. Mariam has received different forms of a gene from each parent. She is said to be ___________ for the trait.a. homozygous c. genusb. heterozygous d. phyla

Chapter Section: Earliest DevelopmentAnswer: b Page(s): 57 Type: AppliedRationale: Inheriting from parents different forms of a gene for a given trait is referred to as heterozygous for that trait. In this example, Mariam has received a different form of the gene for hair color from each parent. Therefore, Mariam is said to be heterozygous for that trait.

3.4 Inheritance in which a combination of multiple gene pairs is responsible for the production of a particular trait is known as ___________ inheritance.a. homozygous c. polygenicb. heterozygous d. monozygotic

Chapter Section: Earliest DevelopmentAnswer: c Page(s): 59 Type: FactualRationale: Inheritance in which a combination of multiple gene pairs is responsible for the production of a particular trait is referred to as polygenic inheritance.

3.5 A child will develop PKU only if the child receives a recessive gene from both parents. PKU is an example of a ___________ trait.a. dizygotic c. dominantb. monozygotic d. recessive

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 58, 59 Type: ConceptualRationale: PKU is a recessive trait disorder that is produced by a single allele. Transmission of PKU is accomplished when a child inherits two recessive genes, one from each parent.

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8 A number of recessive genes, called ___________ genes, are located only on the X chromosome.a. X-linked c. X-unlinkedb. Y-linked d. Y-unlinked

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 59 Type: FactualRationale: Genes that are considered recessive and are located only on the X chromosome are known as X-linked genes.

3.2 An example of an X-linked disease isa. PKU. c. hemophilia.b. Down’s syndrome. d. sickle-cell anemia.

Chapter Section: Earliest DevelopmentAnswer: c Page(s): 59 Type: FactualRationale: Hemophilia, a blood disorder, is produced by X-linked genes. Males are more susceptible to these disorders since they do not have the second X chromosome to counteract the genetic information that produces the disorder.

3.3 The study of the effects of heredity on behavior is known as ___________ genetics.a. environmental c. nurtureb. nature d. behavioral

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 60 Type: FactualRationale: The study of the effects of heredity on behavior is known as behavioral genetics.

3.4 Mongolism, now known as ___________ syndrome, is a disorder produced by the presence of an extra chromosome on the 21st pair. a. Tay-Sachs c. sickle-cell anemiab. Down’s d. fragile X

Chapter Section: Earliest DevelopmentAnswer: b Page(s): 61 Type: FactualRationale: Individuals with Down’s syndrome have an extra chromosome on the 21st pair. Once referred to as mongolism, Down’s syndrome is the most frequent cause of mental retardation.

3.5 A disorder that occurs when a particular gene is injured on the X chromosome that results in mild to moderate mental retardation is known as ___________ syndrome.a. Tay-Sachs c. sickle-cell anemiab. Down’s d. fragile X

Chapter Section: Earliest DevelopmentAnswer: d Page(s): 61 Type: FactualRationale: Fragile X syndrome is a disorder produced by injury to a gene on the X chromosome, producing mild to moderate mental retardation.

3.6 A blood disorder that gets its name from the shape of the red blood cells in those who have it is called ___________.a. Tay-Sachs c. sickle-cell anemiab. Down’s syndrome d. fragile X

Chapter Section: Earliest DevelopmentAnswer: c Page(s): 61 Type: Factual

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Rationale: Sickle-cell anemia is a blood disorder that gets its name from the shape of the red blood cells in those who have it. Symptoms include poor appetite, stunted growth, swollen stomach, and yellowish eyes. People afflicted with the most severe form of the disorder rarely live beyond childhood.9 A disorder for which there is no treatment that produces blindness and muscle degeneration prior to death is

known as ___________.a. Tay-Sachs c. sickle-cell anemiab. Down’s syndrome d. fragile X

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 61 Type: FactualRationale: Tay-Sachs disease is a disorder that produces blindness and muscle degeneration prior to death; there is no treatment for Tay-Sachs.

3.2 A disorder resulting from the presence of an extra X chromosome that results in underdeveloped genitals, extreme height, and enlarged breasts is known as ___________ syndrome.a. Tay-Sachs c. sickle-cell anemiab. Klinefelter’s d. fragile X

Chapter Section: Earliest DevelopmentAnswer: b Page(s): 61 Type: FactualRationale: Klinefelter’s syndrome is a disorder resulting from the presence of an extra X chromosome that produces underdeveloped genitals, extreme height, and enlarged breasts.

3.3 The discipline that focuses on helping people deal with issues relating to inherited disorders is known as ___________ counseling.a. environmental c. bioengineeringb. genetic d. biogenetic

Chapter Section: Earliest DevelopmentAnswer: b Page(s): 62 Type: FactualRationale: Genetic counseling is the discipline that focuses on helping people deal with issues related to inherited disorders.

3.4 The Browns have each inherited a form of cancer from their ancestors. Prior to starting their own family they have been referred for ___________, a discipline that focuses on inherited disorders, to find out the odds that they will pass on cancer to their offspring. a. genetic counseling c. individual counselingb. family counseling d. group counseling

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 62 Type: ConceptualRationale: Genetic counseling is the discipline that focuses on helping people deal with issues related to inherited disorders. The Browns would benefit from investigating the possibility of passing this disease on to their children.

3.5 Concerned about starting a family now that she has turned 40, Gilda is referred to a counselor who uses a variety of data and techniques to advise future parents of possible genetic risks to their unborn children. Gilda was referred to a ___________ counselor.a. guidance c. geneticb. substance abuse d. career

Chapter Section: Earliest DevelopmentAnswer: c Page(s): 62 Type: ConceptualRationale: Genetic counselors focus on helping people deal with issues related to inherited disorders. As an older first-time mother, Gilda would be interested in exploring concerns this may raise for her future children.

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10 The process of identifying genetic defects by examining a small sample of fetal cells drawn by a needle inserted in the amniotic fluid surrounding the unborn fetus is calleda. amniocentesis. c. ultrasound sonography.b. chorionic villus sampling. d. embryoscopy.

Chapter Section: Earliest DevelopmentAnswer: a Page(s): 63 Type: FactualRationale: An amniocentesis is the process of identifying genetic defects by examining a small sample of fetal cells drawn by a needle inserted into the amniotic fluid surrounding the unborn fetus.

3.2 A test used to find genetic defects that involves taking samples of hair-like material that surrounds the embryo is known asa. amniocentesis. c. ultrasound sonography.b. chorionic villus sampling. d. embryoscopy.

Chapter Section: Earliest DevelopmentAnswer: b Page(s): 62, 63 Type: FactualRationale: Chorionic villus sampling (CVS) is a test used to find genetic defects that involves taking samples of hair-like material that surrounds the embryo.

3.3 A process in which high-frequency sound waves scan the mother’s womb to produce an image of the unborn baby, whose size and shape can then be assessed, is calleda. amniocentesis. c. ultrasound sonography.b. chorionic villus sampling. d. embryoscopy.

Chapter Section: Earliest DevelopmentAnswer: c Page(s): 62, 63 Type: FactualRationale: An ultrasound is a process in which high-frequency sound waves scan the mother’s womb to produce an image of the unborn baby, whose size and shape can then be assessed.

3.4 Beyond learning of potential disorders that may be passed on to children, ___________ may also be used to identify future disorders for an individual. An example would be identification of the flawed gene for Huntington’s disease.a. biogenetics c. bioengineeringb. genetic counseling d. environmental counseling

Chapter Section: Earliest DevelopmentAnswer: b Page(s): 64, 65 Type: ConceptualRationale: Genetic counseling is used to help people deal with issues related to inherited disorders. This may entail predicting potential disorders that may affect offspring, but it may also identify future potential disorders for an individual.

3.5 As developmental research accumulates, it is becoming increasingly clear that when thinking about the interaction between heredity and environment, behavior is most likely the result ofa. heredity. c. interaction between heredity and environment.b. environment. d. equal parts heredity and environment.

Chapter Section: The Interaction of Heredity and EnvironmentAnswer: c Page(s): 66 Type: FactualRationale: Increasing research demonstrates that some factor of interaction between heredity and environment are responsible for behavior.

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11 Patterns of arousal and emotionality that are consistent and enduring characteristics in an individual are known as a person’sa. nature. c. disposition.b. character. d. temperament.

Chapter Section: The Interaction of Heredity and EnvironmentAnswer: d Page(s): 67 Type: FactualRationale: Temperament is defined as the patterns of arousal and emotionality that represent consistent and enduring characteristics in an individual.

3.2 The interaction of factors, or ___________ transmission, is the determination of traits by a combination of both genetic and environmental factors in which a genotype provides a range within which a phenotype may be expressed.a. multifactorial c. monofactorialb. bifactorial d. trifactorial

Chapter Section: The Interaction of Heredity and EnvironmentAnswer: a Page(s): 67 Type: FactualRationale: The determination of traits by a combination of both genetic and environmental factors in which a genotype provides a range within which a phenotype may be expressed is known as multifactorial transmission.

3.3 Genetic and environmental factors work in tandem, but their degree of influence differs for different traits. For which of the following traits do a person’s genes have a greater influence as opposed to his or her environment?a. weight c. heightb. intelligence d. personality

Chapter Section: The Interaction of Heredity and EnvironmentAnswer: c Page(s): 67 Type: ConceptualRationale: Certain genotypes are relatively unaffected by environmental factors. In those cases, development follows a preordained pattern, relatively independent of the specific environment in which a person is raised. Of the choices above, height is the trait for which a person’s genes have the greatest influence and environment has the least influence.

3.4 When the sperm and an ovum are joined, a single new cell is formed. This process is known as conception, ora. implantation. c. insemination.b. germination. d. fertilization.

Chapter Section: Prenatal Growth and ChangeAnswer: d Page(s): 75 Type: FactualRationale: Fertilization is the process by which a sperm and an ovum, the male and female gametes, respectively, join to form a single new cell.

3.5 The prenatal period that takes place during the first two weeks following conception is known as the ___________ stage.a. germinal c. fetalb. embryonic d. placenta

Chapter Section: Prenatal Growth and ChangeAnswer: a Page(s): 76 Type: FactualRationale: The first, and slowest, stage of the prenatal period, which takes place during the first two weeks following conception, is the germinal stage.

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12 The order of prenatal development is as follows:a. germinal, embryonic, fetal c. embryonic, germinal, fetalb. fetal, embryonic, germinal d. germinal, fetal, embryonic

Chapter Section: Prenatal Growth and ChangeAnswer: a Page(s): 76 Type: FactualRationale: The prenatal period consists of three phases: the germinal, embryonic, and fetal stages.

3.2 A conduit between the mother and fetus, the __________ provides nourishment and oxygen via the umbilical cord. a. plasma c. placebob. placenta d. protective layer

Chapter Section: Prenatal Growth and ChangeAnswer: b Page(s): 77 Type: FactualRationale: The placenta is a conduit between the mother and fetus, providing nourishment and oxygen via the umbilical cord.

3.3 The period from two to eight weeks following fertilization, during which significant growth occurs in the major organs and body systems, is known as the ___________ stage.a. germinal c. fetalb. embryonic d. placenta

Chapter Section: Prenatal Growth and ChangeAnswer: b Page(s): 76, 77 Type: FactualRationale: The embryonic stage is the period from two to eight weeks following fertilization during which significant growth occurs in the major organs and body systems.

3.4 Major organs and body systems are formed during this period of prenatal development.a. germinal c. fetalb. placenta d. embryonic

Chapter Section: Prenatal Growth and ChangeAnswer: d Page(s): 77 Type: FactualRationale: It is during the embryonic stage that the major organs and basic anatomy develop.

3.5 The period that begins at about eight weeks after conception and continues until birth is known as the ___________ stage.a. germinal c. fetalb. embryonic d. placenta

Chapter Section: Prenatal Growth and ChangeAnswer: c Page(s): 77, 78 Type: FactualRationale: The fetal stage begins about eight weeks after conception and continues until birth.

3.6 From eight weeks after conception until birth, a developing child is known as a(n)a. neonate. c. baby.b. infant. d. fetus.

Chapter Section: Prenatal Growth and ChangeAnswer: d Page(s): 77, 78 Type: FactualRationale: A developing child, from eight weeks after conception until birth, is known as a fetus.

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13 The inability to conceive after 12 to 18 months of trying to become pregnant is known as a. infertility. c. productivity.b. sterility. d. fertility.

Chapter Section: Prenatal Growth and ChangeAnswer: a Page(s): 78 Type: FactualRationale: The inability to conceive after 12 to 18 months of trying to become pregnant is referred to as infertility. Some 15% of couples suffer from infertility.

3.2 A physician places a man’s sperm directly into a woman’s vagina. This method of fertilization is known asa. natural insemination. c. surrogate fertilization.b. artificial insemination. d. in vitro fertilization.

Chapter Section: Prenatal Growth and ChangeAnswer: b Page(s): 79 Type: FactualRationale: Artificial insemination is the process of fertilization in which a man’s sperm is placed directly into a women’s vagina by a physician.

3.3 Juan and Maria Salinas want to have a baby. However, Juan Salinas is paralyzed from the waist down. They decide to have their doctor place Juan’s sperm directly into Maria’s vagina. This method of fertilization is known asa. natural insemination. c. surrogate fertilization.b. artificial insemination. d. in vitro fertilization.

Chapter Section: Prenatal Growth and ChangeAnswer: b Page(s): 79 Type: ConceptualRationale: Artificial insemination is the process of fertilization in which a man’s sperm is placed directly into a women’s vagina by a physician. In this example, Juan’s sperm will be placed directly into Maria’s vagina.

3.4 A procedure in which a woman’s ova are removed from her ovaries, then a man’s sperm are used to fertilize the ova in a laboratory, is known asa. natural insemination. c. surrogate fertilization.b. artificial insemination. d. in vitro fertilization.

Chapter Section: Prenatal Growth and ChangeAnswer: d Page(s): 79 Type: FactualRationale: In vitro fertilization is a procedure in which a woman’s ova are removed from her ovaries, and a man’s sperm are used to fertilize the ova in a laboratory.

3.5 Tina and Russell Stovers want to start a family. However, Tina had her fallopian tubes tied and now is unable to get pregnant. The Stovers have opted for a procedure in which a woman’s ova are removed from her ovaries, and a man’s sperm are used to fertilize the ova in a laboratory. This method of fertilization is known asa. natural insemination. c. surrogate fertilization.b. artificial insemination. d. in vitro fertilization.

Chapter Section: Prenatal Growth and ChangeAnswer: d Page(s): 79 Type: ConceptualRationale: In vitro fertilization is a procedure in which a woman’s ova are removed from her ovaries, and a man’s sperm are used to fertilize the ova in a laboratory.

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14 A woman who agrees to carry a child to term in cases in which the mother who provides the donor eggs is unable to conceive is called a(n) ___________ mother.a. alternative c. surrogateb. step d. substitute

Chapter Section: Prenatal Growth and ChangeAnswer: c Page(s): 79, 80 Type: FactualRationale: A surrogate mother is a woman who agrees to carry a child to term for another woman.

3.2 The Carlos family has agreed to have another woman, Estella, carry their child to term. Estella is a(n) ___________ mother.a. alternative c. surrogateb. step d. substitute

Chapter Section: Prenatal Growth and ChangeAnswer: c Page(s): 79, 80 Type: ConceptualRationale: A surrogate mother is a woman who agrees to carry a child to term for another woman.

3.3 An environmental agent such as a drug, chemical, virus, or other factor that produces a birth defect is called aa. triotogen. c. teratogen.b. biotogen. d. fibrotogen.

Chapter Section: Prenatal Growth and ChangeAnswer: c Page(s): 81 Type: FactualRationale: A teratogen is a factor that produces a birth defect.

3.4 All of the following may influence the severity of the effect of a teratogen on the developing child EXCEPTa. timing of the exposure. c. quantity of the exposure.b. social and cultural context. d. birth order of the child.

Chapter Section: Prenatal Growth and ChangeAnswer: d Page(s): 81 Type: FactualRationale: The timing and quantity of the exposure to the teratogen are critical. In addition, the broader social and cultural context in which teratogen exposure occurs needs to be considered.

3.5 A disorder caused by the pregnant mother consuming substantial quantities of alcohol during pregnancy, potentially resulting in mental retardation and delayed growth in the child, is known asa. fetal alcohol effects. c. fetal alcohol syndrome.b. maternal alcohol effects. d. maternal alcohol syndrome.

Chapter Section: Prenatal Growth and ChangeAnswer: c Page(s): 84 Type: FactualRationale: Fetal alcohol syndrome (FAS) is a disorder caused by the pregnant mother consuming substantial quantities of alcohol during pregnancy, potentially resulting in mental retardation and delayed growth in the child. Fetal alcohol effects (FAE) is a condition in which children display some, although not all, of the problems of fetal alcohol syndrome due to the mother’s consumption of alcohol during pregnancy.

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15 Mika consumed large quantities of alcohol while she was pregnant with her daughter, Jasmine. As a result, Jasmine was born mentally retarded and is delayed in growth. Jasmine hasa. fetal alcohol effects. c. fetal alcohol syndrome.b. maternal alcohol effects. d. maternal alcohol syndrome.

Chapter Section: Prenatal Growth and ChangeAnswer: c Page(s): 84 Type: ConceptualRationale: Fetal alcohol syndrome (FAS) is a disorder caused by the pregnant mother consuming substantial quantities of alcohol during pregnancy, potentially resulting in mental retardation and delayed growth in the child. In this example you would select FAS over fetal alcohol effects because of the indication that Jasmine was mentally retarded and delayed in growth.

Essay Questions

3.2 What is the difference between genotype and phenotype?

Chapter Section: Earliest DevelopmentPage(s): 57 Type: FactualAnswer: A good answer would include the following key points:

Both genotype and phenotype are used to describe genetic traits. Genotype is the actual combination of genetic material present, although not necessarily visible. Phenotype is the observable trait; the trait as it is seen. If you know the genotype, you can predict the phenotype. However, knowing the phenotype does not

guarantee that you can correctly predict the genotype.

3.3 What are some of the methods of data collection that genetic counselors use to advise future parents of possible genetic risks to their unborn children?

Chapter Section: Earliest Development Page(s): 62–65 Type: FactualAnswer: A good answer would include the following key points:

Family history and demographics Physical examination of future parents

Blood, skin, and urine sample analysis Karyotype

In addition, if the woman is already pregnant, the genetic counselor would request appropriate prenatal tests.

3.4 Sickle-cell anemia has been gradually reduced in the United States, but not in West Africa. This discrepancy is an example of a genetic disorder that is influenced by environmental factors. Describe sickle-cell anemia and the reason for the discrepancy between the United States and West Africa.

Chapter Section: Earliest DevelopmentPage(s): 62 Type: ConceptualAnswer: A good answer would include the following key points:

Sickle-cell anemia is a blood disorder that afflicts people of African descent. Symptoms include poor appetite, stunted growth, swollen stomach, and yellowish eyes. People with the most severe form of the disorder do not live beyond childhood. Incidence of sickle-cell anemia is lower in the United States than in West Africa. Sickle cell gene increases immunity to malaria, making the presence of the sickle cell gene an

advantage in West Africa (as opposed to the US).

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16 Should all prospective parents consider genetic counseling? Why or why not? What are some of the ethical considerations with genetic counseling?

Chapter Section: Earliest DevelopmentPage(s): 62–65 Type: AppliedAnswer: The answer for the first question may be either affirmative or negative but should include support for the choice made by the student.

Ethical considerations would include the following key points: Knowledge of genetic predictions can prevent catastrophic disorders, but it may also encourage

genetic engineering. Parents have more diverse decisions to make with knowledge gained through genetic counseling. Disability advocates warn that parents may not consider the whole child and may focus only on

predicted disabilities.

3.2 How are twin, adoption, and family studies used to study the interaction between heredity and environment?

Chapter Section: The Interaction of Heredity and EnvironmentPage(s): 68, 69 Type: ConceptualAnswer: A good answer would include the following key points:

Role of the monozygotic twin studies – identical genetic backgrounds Dizygotic twin studies – some environmental similarities Other family and adoption studies – unique considerations that help to isolate either heredity or

environment

3.3 Some people have used the proven genetic basis of intelligence to argue against strenuous educational efforts on behalf of individuals with below average IQs. Does this viewpoint make sense based on what you have learned about heredity and environment? Why or why not?

Chapter Section: The Interaction of Heredity and EnvironmentPage(s): 67–71 Type: AppliedAnswer: A good answer would include the following key points:

Multifactorial transmission of intelligence Intelligence may be explained by a range of differing possible sources that represent the extent of the

nature–nurture continuum Discussion of the value of environmental influences on intelligence

3.4 Describe the fertilization process.

Chapter Section: Prenatal Growth and ChangePage(s): 75, 76 Type: FactualAnswer: A good answer would include the following key points:

Fertilization is the process by which the sperm and ovum join to form a new cell. The ovum

Women are born with all of the ovum available to them. Around puberty the ovum mature and are released during ovulation.

The sperm Sperm are created in the testicles at a rapid rate, several hundred million sperm a day.

When sperm enters the vagina, they must move through the cervix and into the fallopian tube. Fertilization occurs in the fallopian tube.

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17 What are the stages of prenatal development?

Chapter Section: Prenatal Growth and ChangePage(s): 76–78 Type: FactualAnswer: A good answer would include the following key points:

Prenatal development is divided into three phases. The Germinal phase is from fertilization to 2 weeks.

This is the shortest phase, with rapid cell division. The Embryonic phase is from 2 weeks to 8 weeks.

Embryo develops major organs and anatomy. The Fetal phase is from 8 weeks to birth.

Fetus grows rapidly through birth

3.2 What are the differences between fetal alcohol syndrome (FAS) and fetal alcohol effects (FAE)?

Chapter Section: Prenatal Growth and ChangePage(s): 83, 84 Type: FactualAnswer: A good answer would include the following key points:

Fetal alcohol syndrome (FAS) occurs when the mother’s use of alcohol is substantial, while fetal alcohol effects (FAE) is the result of mothers who consume less alcohol during pregnancy.

FAS has more serious consequences, including below-average intelligence, delayed growth, and facial deformities (mental retardation sometimes occurs).

FAE will display some but not all of the consequences of FAS. Due to the risks associated even with minimal amounts of alcohol, women who are trying to become

pregnant should already refrain from drinking.

3.3 What are some ways that the prenatal environment can threaten development?

Chapter Section: Prenatal Growth and ChangePage(s): 80–84 Type: ConceptualAnswer: A good answer would include the following key points:

Effect of teratogens on prenatal development Consider timing of exposure, strength of exposure

Social and cultural context of prenatal environment Maternal influence

Diet, age, prenatal support, health, use of drugs, alcohol, or tobacco Paternal influence

Use of drugs, alcohol, or tobacco, abusiveness to pregnant partner

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