Question 1

Janaka's two-year-old daughter is intellectually disordered (formerly known as mentally retarded) due, in part, to a diet that included fish, bread, and dairy products. The most likely diagnosis for Janaka's daughter is that she has

Accepted Answer

Phenylketonuria (PKU) is a metabolic disorder caused by a deficiency in the enzyme needed to metabolize phenylalanine, an amino acid found in many foods including fish, bread, and dairy products. If untreated, it can lead to intellectual disability among other symptoms.

Question 2

As dizygotic twins, Maya and Naomi

Accepted Answer

Dizygotic twins, also known as fraternal twins, are formed from two different eggs fertilized by two different sperm, leading them to share about 50% of their genes, similar to siblings born at different times.

Question 3

Which physical characteristic is most indicative of an individual with Down syndrome?

Accepted Answer

A common physical characteristic of individuals with Down syndrome is a fold of skin over each eyelid, known as epicanthic folds.

Question 4

Huntington's disease is an unusual genetic disorder in that it is a fatal disease caused by dominant alleles that

Accepted Answer

Huntington's disease is caused by a dominant allele, and its symptoms typically do not appear until mid-adult life, after individuals may have already reproduced, passing the allele to their offspring.

Question 5

As a geneticist, you found that afetus has 47 chromosomes. What would be the most likely conclusion drawn from this information?

Accepted Answer

The most likely conclusion is that the child has Down syndrome, which is characterized by an extra chromosome 21, resulting in a total of 47 chromosomes instead of the normal 46. Sickle-cell anemia and phenylketonuria (PKU) are genetic disorders caused by specific gene mutations, not by an abnormal number of chromosomes.

Question 6

Which statement best exemplifies the basic premise of behavioral genetics?

Accepted Answer

Behavioral genetics suggests that traits like openness to new experiences are influenced by both genetic and environmental factors, and individuals can exhibit a wide range of behaviors rather than being at one extreme or the other.

Question 7

José, who was adopted at birth, is found to have personality characteristics more similar to his biological mom than to his adoptive mom. How should you interpret this data?

Accepted Answer

Personality characteristics showing more similarity to a biological parent than to an adoptive parent suggest a genetic influence on personality, indicating that genes play a significant role in shaping personality traits.

Question 8

As a behavioral geneticist, Professor Klink is most likely to calculate the extent to which depression is inherited using a ____ coefficient.

Accepted Answer

Heritability coefficients are used by behavioral geneticists to estimate the extent to which genetic differences among individuals contribute to individual differences in observed behaviors or traits, such as depression, within a population.

Question 9

As a behavioral geneticist, Juan would most likely be studying

Accepted Answer

Behavioral geneticists focus on understanding how genetics and environment contribute to behavioral traits and psychological characteristics, making option C the correct answer.

Question 10

After creating a child's DNA profile, behavioral geneticists can then look to see

Accepted Answer

Behavioral geneticists study the relationship between genetic makeup (genotype) and behavioral traits (phenotypes). They can analyze a child's DNA profile to see if certain genetic variations are associated with specific behaviors, not to determine geographic origins, adoption status, or eugenic rankings.

Question 11

Which result would not support the idea that genes play a significant role in behavior?

Accepted Answer

Finding dizygotic (fraternal) twins to be more similar than monozygotic (identical) twins would not support the idea that genes play a significant role in behavior, as monozygotic twins share more genetic material than dizygotic twins.

Question 12

Heredity and environment

Accepted Answer

Heredity and environment interact dynamically throughout development, influencing each other in complex ways from conception through adulthood. This interaction affects all aspects of human growth and development, including physical, cognitive, and emotional development.

Question 13

If a physician informed you that your speech disorder was the result of problems on chromosomes 4, 7, and 15, you would rightly conclude that the disorder is always classifiable as

Accepted Answer

The involvement of multiple chromosomes (4, 7, and 15) in the speech disorder suggests that the condition is polygenetic, meaning it is influenced by several genes. Polygenetic inheritance involves the interaction of multiple genes to produce a trait or disorder, rather than being determined by a single gene.

Question 14

John and Wayne have the exact same genes. This indicates that they must be

Accepted Answer

Monozygotic twins, also known as identical twins, develop from a single fertilized egg that splits into two, leading them to share the exact same genetic material.

Question 15

The concept that genotypes are not the only things that control traits involves the fact that

Accepted Answer

Each genotype can produce a variety of phenotypes depending on environmental influences and interactions, demonstrating that traits are not solely determined by genotypes.

Question 16

Which individual with a genetic predisposition toward being extroverted is demonstrating successful niche-picking?

Accepted Answer

Wink, as a game-show host, is likely to be in an environment that suits an extroverted personality, allowing for social interaction and public speaking, which aligns with the concept of niche-picking where individuals select environments that complement their predispositions.

Question 17

_________ occurs when an individual intentionally seeks out an environment that matches characteristics driven by his or her genes.

Accepted Answer

Niche-picking refers to the process where individuals seek out environments that are compatible with their genetic predispositions. This behavior ensures that the environments they choose to engage in are more likely to complement and enhance their genetic tendencies.

Question 18

A heritability coefficient of ____ means about 50 percent of the difference between people on a specific characteristic is the result of heredity.

Accepted Answer

A heritability coefficient of .5 (or 50%) indicates that approximately 50 percent of the variance observed in a specific trait among individuals in a population can be attributed to genetic differences.

Question 19

Because of his accurate knowledge of genetics and disorders, Benson knows that his newborn son has no chance of having

Accepted Answer

Turner's syndrome is a condition that affects only females, as it involves the complete or partial absence of one of the X chromosomes. Since Benson's child is a son, he cannot have Turner's syndrome.

Question 20

Nonshared environmental influences involve forces that make siblings

Accepted Answer

Nonshared environmental influences are those factors that contribute to differences among siblings, making them unique from each other.

Quiz 2: Biological Foundations: Heredity, Prenatal Development, and Birth