Question 1

An individual with an extra chromosome on the 21st pair of chromosomes has _____.
A) Down syndrome
B) nearsightedness
C) fragile X syndrome
D) Tourette syndrome

Accepted Answer

An extra chromosome on the 21st pair of chromosomes is also known as trisomy 21, which results in Down syndrome.

Question 2

Eight-year-old Joe has no difficulty seeing things near him but sometimes struggles to see things in the distance. Joe gets his eyes checked and is told that he does not yet need corrective lenses for nearsightedness. Instead, drawing on current research, the ophthalmologist advises that he _____.
A) do homework in a very brightly lit room
B) watch television on a larger screen
C) play outside more
D) avoid reading small print

Accepted Answer

The ophthalmologist advises that Joe should play outside more because research suggests that spending more time outdoors in natural light may help prevent or delay the onset of myopia (nearsightedness) in children.

Question 3

The heritability for human traits, such as nearsightedness, _____.
A) is the same in every culture
B) can differ between cultures
C) is not influenced by cultural factors
D) will always be different between cultures

Accepted Answer

Heritability can differ between cultures because cultural factors, such as access to education and exposure to environmental factors like sunlight, can influence the expression of certain traits.

Question 4

The cognitive deficits caused by the genetic condition of _____ are the most common form of inherited mental retardation.
A) Down syndrome
B) nearsightedness
C) fragile X syndrome
D) Huntington's disease

Accepted Answer

Fragile X syndrome is a genetic condition that affects the X chromosome and is the most common form of inherited mental retardation. It is caused by a mutation in the FMR1 gene, which affects the production of a protein necessary for normal brain development. Individuals with fragile X syndrome may experience cognitive deficits, learning disabilities, and developmental delays.

Question 5

Sally is born with 47 chromosomes instead of the usual 46. Sally's chances of survival are about 1 in _____.
A) 16
B) 166
C) 316
D) 456

Accepted Answer

Sally has Down syndrome, which is caused by an extra copy of chromosome 21. The incidence of Down syndrome is approximately 1 in 166 live births. Therefore, Sally's chances of survival are about 1 in 166.

Question 6

Individuals who may especially benefit from preconception, prenatal, or even prenuptial (before marriage) genetic counseling include all the following EXCEPT _____.
A) women over age 35 and men over age 40
B) couples who are infertile
C) couples who have had several spontaneous abortions or stillbirths
D) women who are younger than 25 and men who are younger than 30

Accepted Answer

While all individuals may benefit from genetic counseling, women over age 35 and men over age 40, couples who are infertile, and couples who have had several spontaneous abortions or stillbirths are all considered high-risk groups for genetic disorders due to increasing age and/or previous reproductive complications. Therefore, option D, which includes individuals who are younger than 25 and 30, is the only option that does not fit this high-risk category.

Question 7

Ways in which chromosomal and genetic problems are relevant to human development include all the following EXCEPT _____.
A) they provide insight into the complexities of nature and nurture
B) information combats prejudice: Difference is not always deficit
C) knowing that nature influences means that nurture can be ignored
D) knowing the origins helps limit their effects

Accepted Answer

Option C is incorrect because knowing that nature influences human development does not mean that nurture can be ignored. Nurture can still have a significant impact on development, even when genetic or chromosomal issues are present. The other options are all relevant reasons for understanding chromosomal and genetic problems in human development.

Question 8

The statistic that indicates how much of the variation in a particular trait can be traced to genes is called "_____."
A) a correlation
B) heritability
C) the mean
D) probability

Accepted Answer

Heritability is the statistic that represents the proportion of variation in a particular trait that is attributed to genetics. A correlation measures the strength and direction of the relationship between two variables, the mean is the average of a set of scores, and probability measures the likelihood of an event occurring.

Question 9

Approximately once in every _____ births, a newborn survives with 45, 47, or even 48 or 49 chromosomes instead of the usual 46.
A) 16
B) 166
C) 316
D) 456

Accepted Answer

Chromosomal abnormalities such as having 45, 47, or more chromosomes occur in approximately 1 in 166 births.

Question 10

Most recessive genetic disorders are _____.
A) on the autosomes
B) X-linked
C) additive
D) polygenic

Accepted Answer

Most recessive genetic disorders are caused by mutations on autosomes, which are the non-sex chromosomes. X-linked disorders are also possible, but they are less common than autosomal recessive disorders. Additive and polygenic disorders are not necessarily recessive and can be inherited in different ways.

Question 11

Which mother is at greatest risk of having a child with a chromosomal abnormality?
A) a 15-year-old mother
B) a 25-year-old mother
C) a 35-year-old mother
D) a 45-year-old mother

Accepted Answer

The risk of chromosomal abnormalities, such as Down syndrome, increases with maternal age, making a 45-year-old mother the most at risk.

Question 12

Which of the following is an example of a single-gene disorder that is dominant?
A) Down syndrome
B) nearsightedness
C) fragile X syndrome
D) Huntington's disease

Accepted Answer

Huntington's disease is a single-gene disorder that is caused by a dominant allele. This means that if a person inherits just one copy of the mutated gene, they will develop the disease.

Question 13

Most of the known single-gene disorders are _____.
A) recessive
B) dominant
C) difficult to identify
D) additive

Accepted Answer

The answer of Most of the known single-gene disorders are...

Question 14

Consultation and testing by trained experts that enable individuals to learn about their genetic heritage, including harmful conditions they could pass along to any children they might conceive, is referred to as "_____."
A) couples counseling
B) marriage counseling
C) genetic counseling
D) individual counseling

Accepted Answer

Genetic counseling is a process where trained experts provide information and testing to help individuals learn about their genetic heritage. This includes identifying any harmful conditions or genetic disorders they may carry and could potentially pass on to their children. It is not the same as couples counseling or marriage counseling, which focus on improving communication and resolving conflicts in a relationship. Genetic counseling may be offered to individuals or couples, but it specifically focuses on genetic information rather than general mental or emotional health concerns, which would be addressed in individual counseling.

Question 15

Knowing that nature and nurture affect every human trait and disorder means all the following EXCEPT _____.
A) no one should be blamed or punished for inherited problems
B) prevention efforts may decrease the occurrence of the trait or disorder
C) ignoring the nature-nurture influence on human traits and disorders can be lethal
D) nurture can always override the potential influence of nature

Accepted Answer

Nurture cannot always override the potential influence of nature. There are some traits, such as genetic disorders, that cannot be overridden by nurture alone. Both nature and nurture play significant roles in shaping human traits and disorders.

Question 16

The most common extra-chromosome condition is _____.
A) Down syndrome
B) nearsightedness
C) fragile X syndrome
D) Tourette syndrome

Accepted Answer

Down syndrome, also known as trisomy 21, is the most common extra-chromosome condition, where individuals have three copies of chromosome 21 instead of the usual two. It is characterized by intellectual disability, characteristic facial features, and increased risk for certain medical conditions.

Question 17

Down syndrome is also called "_____."
A) trisomy-12
B) trisomy-13
C) trisomy-21
D) trisomy-31

Accepted Answer

Down syndrome is caused by the presence of an extra copy of chromosome 21, also known as trisomy-21. This results in characteristic physical features and intellectual disability. Trisomy-12 and trisomy-13 are also chromosomal abnormalities, but they result in different conditions with distinct characteristics. Trisomy-31 is not a known chromosomal abnormality.

Question 18

Eyeballs change shape at typical stages of development, including puberty and middle adulthood. This makes it more likely that _____ will increase at puberty, and _____ will decrease during middle adulthood.
A) nearsightedness; farsightedness
B) farsightedness; nearsightedness
C) nearsightedness; nearsightedness
D) farsightedness; farsightedness

Accepted Answer

The answer of Eyeballs change shape at typical stages of...

Question 19

A fatal central nervous system disorder caused by a copy number variation-more than 35 repetitions of a particular set of three base pairs-is _____.
A) Down syndrome
B) nearsightedness
C) fragile X syndrome
D) Huntington's disease

Accepted Answer

The disorder described in the question is Huntington's disease, which is caused by a CAG trinucleotide repeat expansion in the huntingtin gene. This expansion leads to the production of a mutated form of the huntingtin protein, which accumulates in certain neurons in the brain and causes their degeneration, leading to symptoms such as involuntary movements, psychiatric disturbances, and cognitive decline. Down syndrome is a chromosomal disorder caused by an extra copy of chromosome 21, while fragile X syndrome is caused by a mutation in the FMR1 gene that leads to a reduced production of the fragile X mental retardation protein (FMRP) and is characterized by intellectual disability, behavioral problems, and physical features such as a long face and large ears. Nearsightedness, or myopia, is a refractive error of the eye that causes distant objects to appear blurry.

Question 20

About one in every _____ infants is born with only one sex chromosome or with three or more, which creates a chromosomal abnormality.
A) 100
B) 300
C) 500
D) 700

Accepted Answer

About one in every 300 infants is born with a chromosomal abnormality. This includes conditions such as Turner syndrome (one X chromosome), Klinefelter syndrome (two or more X and/or Y chromosomes), and triple X syndrome (three X chromosomes).

Quiz 3: Heredity and Environment

An individual with an extra chromosome on the 21st pair of chromosomes has _____.

Eight-year-old Joe has no difficulty seeing things near him but sometimes struggles to see things in the distance. Joe gets his eyes checked and is told that he does not yet need corrective lenses for nearsightedness. Instead, drawing on current research, the ophthalmologist advises that he _____.

The heritability for human traits, such as nearsightedness, _____.

The cognitive deficits caused by the genetic condition of _____ are the most common form of inherited mental retardation.

Sally is born with 47 chromosomes instead of the usual 46. Sally's chances of survival are about 1 in _____.

Individuals who may especially benefit from preconception, prenatal, or even prenuptial (before marriage) genetic counseling include all the following EXCEPT _____.

Ways in which chromosomal and genetic problems are relevant to human development include all the following EXCEPT _____.

The statistic that indicates how much of the variation in a particular trait can be traced to genes is called "_____."

Approximately once in every _____ births, a newborn survives with 45, 47, or even 48 or 49 chromosomes instead of the usual 46.

Most recessive genetic disorders are _____.

Which mother is at greatest risk of having a child with a chromosomal abnormality?

Which of the following is an example of a single-gene disorder that is dominant?

Most of the known single-gene disorders are _____.

Consultation and testing by trained experts that enable individuals to learn about their genetic heritage, including harmful conditions they could pass along to any children they might conceive, is referred to as "_____."

Knowing that nature and nurture affect every human trait and disorder means all the following EXCEPT _____.

The most common extra-chromosome condition is _____.

Down syndrome is also called "_____."

Eyeballs change shape at typical stages of development, including puberty and middle adulthood. This makes it more likely that _ will increase at puberty, and _ will decrease during middle adulthood.

A fatal central nervous system disorder caused by a copy number variation-more than 35 repetitions of a particular set of three base pairs-is _____.

About one in every _____ infants is born with only one sex chromosome or with three or more, which creates a chromosomal abnormality.