Question 1

Which of the following most clearly demonstrates the influence of environment?

Accepted Answer

Sally's walking like her adoptive mother suggests that environmental factors such as observation and mimicry can have a significant impact on behavior. The other examples involve genetic factors (A and C) or a mixture of genetic and environmental factors (D).

Question 2

Despite many variations in environmental conditions and rearing practices,most children learn to walk at about the same time and in the same sequence.We would say that walking is a ______ trait.

Accepted Answer

A trait is considered canalized if it is strongly tied to a particular genotype and therefore is relatively insensitive to environmental influences. In this case, walking is strongly linked to a particular genotype and follows a consistent sequence of developmental milestones regardless of variations in rearing practices or environmental conditions.

Question 3

Brynn carries the gene for heart disease.She now believes that no matter what steps she takes to protect her health,she will have a heart attack in the future.Brynn's misconception is known as

Accepted Answer

Brynn's belief that she will have a heart attack in the future no matter what steps she takes is an example of genetic determinism, which is the mistaken belief that genes determine everything about a person's life and health. This belief ignores the influence of environmental factors and individual choices on health outcomes.

Question 4

Doug has been recruited for a family study looking at the heritability of personality traits.Who else will most likely be included in the study?

Accepted Answer

Family studies typically involve the study of traits across siblings or other close relatives, as they share a significant amount of genetic material. The study would be focused on comparing the personality traits between Doug and his siblings to determine the heritability of these traits.

Question 5

Although Roberto's adoptive parents are short in stature,he is growing to be tall like his biological mother.What might we conclude about Roberto's height?

Accepted Answer

The fact that Roberto is growing to be tall like his biological mother suggests that his height is influenced primarily by hereditary factors. This is because height is a complex trait that is heavily influenced by genetics. However, environmental factors such as nutrition can also play a role in determining height to some extent. The information given does not provide enough evidence to conclude that independent segregation or nutrition is a primary factor in Roberto's height.

Question 6

A karyotype is a(n)

Accepted Answer

A karyotype is a photographic chart of chromosomal abnormalities. It shows the number, size, and shape of chromosomes in an individual's cells. It can help diagnose genetic disorders and provide information about an individual's sex, as well as identify abnormalities such as extra or missing chromosomes.

Question 7

Depending on environmental conditions,the potential variability in the expression of a hereditary trait is called

Accepted Answer

The potential variability in the expression of a hereditary trait due to environmental conditions is called reaction range. Canalization refers to the degree to which the expression of a trait is resistant to environmental variation. Genetics refers to the study of inherited traits and genes. Environmental interaction refers to the ways in which environmental factors can affect the expression of genes. Therefore, only option C accurately reflects the concept described in the question.

Question 8

Which of the following statements about the influences of heredity and environment is correct?

Accepted Answer

A person's potential range of height is mostly determined by genetics, but actual height may be influenced by environmental factors such as nutrition. This means that while genetics play a significant role in determining a person's ultimate height potential, environmental factors can impact whether that potential is fully realized. However, it is not accurate to say that improved nutrition can increase the upper limit or range of height beyond a person's genetic potential, which is why option C is incorrect. Option D is also incorrect because while nutrition is important, it is not necessarily more important than genetic factors in determining height.

Question 9

Scientists generally accept that

Accepted Answer

The most widely accepted view is that human development is shaped by both hereditary factors and environmental factors, and that they constantly interact with one another throughout the lifespan.

Question 10

Klinefelter syndrome and Turner syndrome are caused by abnormalities of the

Accepted Answer

Klinefelter syndrome and Turner syndrome are both caused by abnormalities of the sex chromosomes. In Klinefelter syndrome, individuals have an extra X chromosome (XXY) while in Turner syndrome, individuals only have one X chromosome (X0).

Question 11

It eventually may be possible to treat inherited diseases by repairing or replacing abnormal genes through

Accepted Answer

Gene therapy involves repairing or replacing abnormal genes to treat genetic diseases, whereas genetic counseling involves providing advice and guidance to individuals who may be at risk of inherited diseases. Genome replication and phoneme therapy are not relevant to treating genetic diseases.

Question 12

In attempting to study the degree to which genetics influences activity levels in newborns,a researcher compares monozygotic and dizygotic twins for their level of similarity on that trait.This research is attempting to determine the _____ of the trait activity levels.

Accepted Answer

The research is attempting to determine the heritability of the trait activity levels by comparing the similarity in activity levels between monozygotic (identical) and dizygotic (fraternal) twins. Since monozygotic twins share 100% of their genetic material whereas dizygotic twins share only 50%, any similarities seen in activity levels between monozygotic twins are likely due to genetics, and heritability can be estimated. Therefore, the best choice is D, heritability. Phenotype refers to the physical expression of an individual's genetic makeup, genotype refers to an individual's genetic makeup, and karyotype refers to the number and appearance of chromosomes in the nucleus of a eukaryotic cell.

Question 13

A chromosomal disorder characterized by moderate-to-severe mental retardation and a downward-sloping skin fold at the inner corners of the eyes is called

Accepted Answer

Down syndrome is characterized by the presence of an extra chromosome 21, which causes moderate-to-severe mental retardation and a characteristic facial appearance that includes a downward-sloping skin fold at the inner corners of the eyes. Cystic fibrosis is a genetic disorder that affects the lungs, pancreas, and other organs, Tay-Sachs disease is a rare genetic disorder that affects the nervous system, and sickle-cell anemia is an inherited blood disorder. None of these disorders are associated with the specific symptoms described in the question.

Question 14

Susan and Betty are monozygotic twins,whereas Ming and Li are dizygotic twins.If a particular trait is determined primarily by hereditary factors,what would be the relative degree of concordance in these two twin pairs?

Accepted Answer

Monozygotic twins are genetically identical because they came from a single fertilized egg that split into two, while dizygotic twins developed from two separate eggs and have only 50% of their genes in common. Therefore, monozygotic twins have a higher degree of genetic similarity than dizygotic twins. If a trait is determined primarily by hereditary factors, monozygotic twins are more likely to be concordant (i.e., to share the trait) than dizygotic twins. Thus, Susan and Betty, being monozygotic, would be more concordant than Ming and Li, who are dizygotic.

Question 15

A statistical estimate of how much heredity influences individual differences in a specific trait at a certain time within a given population is referred to as

Accepted Answer

Heritability refers to the degree to which individual differences in a specific trait can be attributed to genetic factors within a certain population at a certain time. It is a statistical estimate and does not imply that a certain percentage of an individual's trait is solely determined by genetics.

Question 16

Which of the following is NOT the responsibility of a genetic counselor?

Accepted Answer

While a genetic counselor can present options and provide information about the risks and benefits of each option, they cannot advise a client on which course of action to take. The final decision is ultimately up to the client or patient.

Question 17

The misconception that individuals with a specific gene are destined to inherit that disease is called

Accepted Answer

Genetic determinism is the belief that an individual's genetic makeup completely dictates their physical and behavioral traits, including their risk for certain diseases. However, this is a misconception as many factors, such as environmental influences and lifestyle choices, can also affect disease risk.

Question 18

Which child is likely to exhibit the smallest reaction range for the trait of intelligence?

Accepted Answer

A child born with severe brain damage is likely to have limited potential for intellectual development, resulting in a small reaction range for intelligence.

Question 19

Which of the following statements regarding Down syndrome is FALSE?

Accepted Answer

This statement is false. Paternal genetic abnormalities can also contribute to the development of Down syndrome, although the majority of cases are associated with the mother's ovum. The risk of having a child with Down syndrome increases with both maternal and paternal age.

Question 20

The quantitative study of relative hereditary and environmental influences on behavior is called

Accepted Answer

The field of studying the relative contributions of genetic and environmental factors to behavior is called behavioral genetics. It involves quantitative studies to understand the heritability of traits, as well as the role of the environment in shaping behavior. Other options like genetic testing, qualitative genetic research, and cognitive genetics, may be related to genetics but do not specifically address the study of both hereditary and environmental influences on behavior.

Quiz 3: Forming a New Life: Conception,heredity,and Environment