Deck 3: Section 2: Biology and Behavior

Question 1

The text reports that the current best estimate is that humans have approximately _____ genes.

A) 21 000
B) 35 000
C) 100 000
D) 275 000

Answer 1

A

Question 2

The structure of DNA was identified by _____ and a colleague.

A) James Watson
B) Gregor Mendel
C) John Stuart Mill
D) Francis Galton

Answer 2

A

Question 3

Genes are sections of:

A) chromosomes.
B) proteins.
C) genotypes.
D) phenotypes.

Answer 3

A

Question 4

In a study of eminent men, Francis Galton concluded that achievement and talent are:

A) predominantly due to the environment.
B) predominantly due to heredity.
C) due to a combination of environment and heredity.
D) due to an interaction of environment and heredity.

Question 5

Genes code for:

A) the production of proteins.
B) specific behaviours.
C) the construction of DNA.
D) traits.

Question 6

Individuals receive _____ copy(ies) of each gene from their mothers.

A) one
B) two
C) three
D) four

Question 7

With the exception of the genes on the X and Y chromosomes, how many copies of each type of gene does an individual generally carry?

A) one
B) two
C) three
D) four

Question 8

Which factor(s) is a direct contributor to a child's phenotype?

A) child's genotype and parents' phenotype
B) child's environment
C) parents' genotype
D) child's genotype and environment

Question 9

Which statement about sex determination is true?

A) The mother's egg always determines the sex of the offspring.
B) The father's sperm always determines the sex of the offspring.
C) Sometimes it is the mother's egg and sometimes it is the father's sperm that determines the sex of the offspring.
D) The mother's egg and the father's sperm jointly determine the sex of the offspring.

Question 10

Which statement about genetics is true?

A) DNA is made up of two twisted chromosomes.
B) Genes are made up of two twisted chromosomes.
C) Chromosomes are made up of two twisted strands of DNA.
D) Genes are made up of two twisted strands of DNA.

Question 11

The mapping of the human genome has resulted in the insight that humans share a large proportion of their genes with:

A) bacteria.
B) fish.
C) elephants.
D) all of these.

Question 12

As reported in the text, the current scientific understanding is that protein-coding genes make up approximately what percentage of the human genome?

A) 2%
B) 20%
C) 96%
D) 100%

Question 13

Which factor is a direct contributor to a child's genotype?

A) parents' genotype
B) parents' phenotype
C) child's phenotype
D) all of these factors

Question 14

The majority of human genes are devoted to making human beings:

A) male or female.
B) primates.
C) animals.
D) humans.

Question 15

The complete set of genes is referred to as a:

A) genome.
B) genesis.
C) genotype.
D) genode.

Question 16

Which statement about genetics is true?

A) Genes are sections of chromosomes.
B) Chromosomes are sections of genes.
C) Chromosomes are sections of DNA.
D) DNA is a section of a gene.

Question 17

The observable expression of an individual's genetic material is referred to as the individual's:

A) genome.
B) genotype.
C) phenotype.
D) environment.

Question 18

Which statement BEST characterizes current scientific thought on the human genome?

A) The greatest portion of the genome is made up of what is now considered "junk" DNA.
B) A small part of the genome is made up of protein-coding genes, and a much larger part regulates the activity of genes.
C) The genome is split about evenly between protein-coding genes and "junk" DNA.
D) The majority of the genome is made up of protein-coding genes, and a much smaller part is made up of noncoding DNA.

Question 19

Pamela and her mother both have a strong aversion to cheese. Consider these paths. Path A: Pamela genetically inherited "cheese aversion" from her mother. Path B: Pamela's mother's own genetically inherited "cheese aversion" led her to create a "cheese aversion" environment in which Pamela developed. Path C: Pamela's mother's aversion to cheese caused Pamela's genotype to change. Which path(s) could have caused this similarity between Pamela and her mother in their strong aversion to cheese?

A) both Paths A and B
B) both Paths A and C
C) both Paths B and C
D) Path B only

Question 20

Children share _____ of their genetic material with each of their grandparents.

A) one-half
B) one-third
C) one-quarter
D) one-eighth

Question 21

Sex-linked disorders associated with the X chromosome are:

A) more likely to affect males.
B) more likely to affect females.
C) equally likely to affect males and females.
D) a result of fragile X syndrome.

Question 22

_____ genes are expressed when an individual is heterozygous for a trait that follows a Mendelian inheritance pattern.

A) Recessive
B) Dominant
C) Polygenic
D) Allele

Question 23

A male zygote has the _____ pattern of sex chromosomes.

A) XX
B) XY
C) YY
D) XY or YY

Question 24

Which factor is the basis of evolution?

A) random assortment of chromosomes
B) mutations
C) the process of crossing over
D) all of these factors

Question 25

Kody, a boy, and Shakira, a girl, are brother and sister. They both inherit the same recessive allele for Trait T on their X chromosome from their mother. What is the relative likelihood of Kody and Shakira expressing Trait T?

A) Both Kody and Skakira are likely to express Trait T.
B) Kody is more likely than is Shakira to express Trait T.
C) Shakira is more likely than is Kody to express Trait T.
D) Neither Kody nor Shakira is likely to express Trait T.

Question 26

In regard to the chromosomes that parents pass on to their offspring, parents pass on:

A) exact copies of their chromosomes to their offspring.
B) exact copies of their chromosomes to their offspring, except when a mutation occurs in the offspring's genes.
C) chromosomes that are constituted differently than their own because of random shuffling and crossing over.
D) exact copies of their chromosomes to their offspring, but the genes are expressed differently because of patterns of dominance.

Question 27

A change in a section of DNA that is the result of either a random, spontaneous error or environmental factors is referred to as:

A) polygenic inheritance.
B) a dominant-recessive pattern.
C) random assortment.
D) a mutation.

Question 28

The gene that codes for Characteristic X has two alleles. Allele D is dominant, and Allele r is recessive. If the father is homozygous for Trait X with Allele r and the mother is heterozygous for Trait X, the chance that one of their offspring will exhibit form r for Trait X is _____.

A) 0%
B) 25%
C) 50%
D) 75%

Question 29

Developmental changes such as puberty, graying hair, and the reduced organ capacity that comes with age are caused in part by:

A) norm of reaction.
B) homozygous alleles.
C) polygenic inheritance.
D) regulator genes.

Question 30

Regulator genes are responsible for:

A) ensuring that all of the sperm's genetic material is inserted into the egg.
B) activating and deactivating other genes.
C) determining which genes go into which cell.
D) establishing an embryo's sex.

Question 31

Geneticist Geri notices that a woman exhibits Trait L. With certainty, she asks the woman, "Which of your parents also exhibits this trait?" The woman is surprised that Geri knew that one of her parents had to also display Trait L. Knowing which fact would have cleared up the woman's confusion?

A) Trait L is governed by a dominant allele.
B) Trait L is governed by a recessive allele.
C) Trait L involves polygenic inheritance.
D) None of these would help to clear up the confusion.

Question 32

Which statement about genes is true?

A) Genes that are turned off by regulator genes remain off for the remainder of the person's life.
B) Regulator genes function without input from the environment.
C) Genes belong to extensive networks of genes and do not function in isolation.
D) All of the statements are true.

Question 33

Crossing over refers to:

A) the development of female genitalia by an XY zygote.
B) a process by which two members of a chromosomal pair swap sections of DNA.
C) the random shuffling of the members of the 23 chromosomal pairs in the formation of egg and sperm.
D) a change in a section of DNA caused by environmental factors.

Question 34

If an individual is heterozygous for a trait, he has inherited two:

A) of the same allele for that trait.
B) different alleles for that trait.
C) dominant alleles for that trait.
D) recessive alleles for that trait.

Question 35

Which list is the correct order of events in the development of a male?

A) Y chromosome encodes protein, production of testosterone, prenatal formation of testes
B) Y chromosome encodes protein, prenatal formation of testes, production of testosterone
C) prenatal formation of testes, Y chromosome encodes protein, production of testosterone
D) production of testosterone, Y chromosome encodes protein, prenatal formation of testes

Question 36

A recessive gene governs Trait M. If a child exhibits Trait M, then:

A) both her parents must have also exhibited Trait M.
B) both her parents must have the recessive gene for Trait M.
C) one of her parents has the gene for Trait M.
D) the child has to have a dominant gene for Trait M.

Question 37

Different forms of a gene are referred to as:

A) alleles.
B) regulators.
C) recessive genes.
D) chromosomes.

Question 38

Which statement about gene expression is true?

A) All genes possessed by an individual are expressed continuously.
B) All genes contained in a particular cell are expressed in that cell, but not all genes are contained in every cell.
C) Some genes are expressed for only a short period of the cell's life.
D) All genes possessed by an individual are expressed at some point in the individual's life.

Question 39

Which statement about mutations is true?

A) Mutations may make an individual more likely to survive long enough to produce offspring.
B) Mutations always occur in germ cells.
C) Mutations are the only source of genetic disease.
D) Mutations are created when two members of a pair of chromosomes swap pieces of DNA.

Question 40

Which statement about sex determination is true?

A) The presence of two X chromosomes makes an individual female.
B) The presence of a single X chromosome makes an individual male.
C) The presence of a Y chromosome makes an individual female.
D) The presence of a Y chromosome makes an individual male.

Question 41

Many psychiatric and behavioural disorders are believed to involve:

A) gene anomalies.
B) polygenic inheritance.
C) Mendelian patterns.
D) chromosomal anomalies.

Question 42

Polygenic inheritance refers to:

A) a single gene affecting multiple traits.
B) the blending of genes in heterozygous individuals.
C) dominant-recessive patterns of inheritance.
D) the combined action of multiple genes.

Question 43

Psychological traits, such as empathy, aggression, and shyness, follow the _____ type of inheritance pattern.

A) dominant-recessive
B) X-linked
C) polygenic
D) heterozygous

Question 44

All the outcomes that could theoretically result from a given genotype are referred to as the:

A) polygenic inheritance.
B) genotype-environment interaction.
C) phenotype.
D) norm of reaction.

Question 45

A disorder in which an individual is born with female genitalia but is found to be genetically male may be a result of:

A) a faulty dominant-recessive pattern.
B) Klinefelter syndrome.
C) a defect in regulator genes.
D) a sex-linked disorder.

Question 46

Identical twins Ilyse and Lauren both have a gene for Trait H. The gene for Trait H is expressed only when a child eats rice before the age of 2. Ilyse and Lauren are separated at birth, and Ilyse lives in Japan, where babies begin eating rice at an early age. Lauren lives in Canada, and she is not given rice before the age of 2. Ilyse develops Trait H, whereas Lauren does not develop the trait. This is an example of:

A) polygenic inheritance.
B) genotype-environment interaction.
C) phenotypical variety.
D) the dominant-recessive pattern of inheritance.

Question 47

The research on the effects of abusive parenting on children with a particular genotype demonstrated that:

A) child abuse is genetically inherited.
B) specific genetic risk factors can make some individuals more susceptible than others to particular environmental events.
C) some people have a greater extent of brain plasticity than do others.
D) children's phenotypes lead them to be active creators of their own environments.

Question 48

The influence of the child's _____ on his or her _____ represents the active child theme.

A) genotype; phenotype
B) environment; phenotype
C) phenotype; environment
D) genotype; environment

Question 49

Disease W is a recessive gene disease. Individuals with _____ will suffer from Disease W.

A) one Disease W gene and one healthy gene
B) two Disease W genes
C) two healthy genes
D) two Disease W genes and one healthy gene

Question 50

A clear relationship between the severity of the gene anomaly and the resulting phenotype is displayed by examining the genetic underpinnings of:

A) Down syndrome.
B) Williams syndrome.
C) Klinefelter syndrome.
D) all of these.

Question 51

Phenylketonuria originates from:

A) a chromosomal anomaly.
B) sex-linked inheritance.
C) a dominant-recessive pattern.
D) polygenic inheritance.

Question 52

The manner in which individuals develop phenylketonuria is an example of:

A) genotype-environment interaction.
B) phenotype-environment interaction.
C) direct inheritance.
D) polygenic inheritance.

Question 53

Which disorder involves sex chromosomes?

A) Down syndrome
B) sickle-cell anemia
C) Klinefelter syndrome
D) Williams syndrome

Question 54

Down syndrome originates from:

A) chromosomal anomalies.
B) polygenic inheritance.
C) dominant-recessive patterns.
D) gene anomalies.

Question 55

There are 500 children living in a town in New Brunswick. Approximately how many of these children are likely to meet the criteria for Autism Spectrum Disorder?

A) 1
B) 5
C) 10
D) 50

Question 56

Which property is a mechanism for genetic inheritance of disease?

A) combined action of multiple genes
B) dominant-recessive patterns
C) sex-linked inheritance
D) all of these properties

Question 57

Which effect(s) is an example of the relationship between the child's phenotype and the child's environment? Effect A: effect of the environment created by the child's parents on the child's behaviour. Effect B: effect of the child's interests on the environment the child seeks out. Effect C: effect of the child's behaviour on the parents' responses to the child.

A) both Effects A and B
B) both Effects A and C
C) both Effects B and C
D) Effects A, B, and C

Question 58

A person who has a genetic disorder that results from a chromosomal anomaly possesses:

A) two recessive genes for the disorder.
B) extra or missing genes.
C) multiple genes that code for the disorder.
D) more or fewer than the normal number of chromosomes.

Question 59

When several genes contribute to a particular phenotypic outcome, this is referred to as:

A) Mendelian inheritance.
B) a heterozygous inheritance.
C) multifactorial expression.
D) polygenic inheritance.

Question 60

Which statement about traits that involve polygenic inheritance is true?

A) These traits are passed down from either the mother or the father directly to the offspring.
B) These traits are expressed only if an individual has a dominant gene.
C) Offspring have a one-in-four chance of possessing a trait if the parents possess it.
D) None of these statements is true.

Question 61

Epigenetics is MOST relevant to which relationship?

A) child's environment‒child's phenotype
B) child's phenotype‒child's environment
C) child's genotype‒child's phenotype
D) child's environment‒child's genotype

Question 62

If the correlation between identical twins on Trait R is higher than the correlation between fraternal twins on Trait R, behaviour geneticists conclude that:

A) genetic factors are important in the development of Trait R.
B) genetic factors are irrelevant to the development of Trait R.
C) environmental factors are irrelevant in the development of Trait R.
D) genetic factors and environmental factors play equivalent roles in the development of Trait R.

Question 63

Which statement is true?

A) Mutations aside, the structure of DNA remains fixed throughout one's life.
B) Epigenetic mechanisms can alter the expression of genes.
C) Changes in the expression of genes can be passed on to offspring.
D) None of these statements is true.

Question 64

Eddie and Freddy are identical twins who grew up in the same home in Nova Scotia but then went their separate ways after high school. Eddie moved to Manitoba and became a family farmer. Freddy moved to Toronto and became a high-powered lawyer. A university research project measures their DNA methylation levels at age 6, age 36, and age 60. Which statement MOST likely reflects the results?

A) Eddie and Freddy will have virtually no differences in their methylation levels.
B) Eddie and Freddy will have vastly different methylation levels at all ages.
C) Eddie and Freddy's methylation levels at age 6 will be similar, but will diverge as they get older.
D) There is no way to predict Eddie and Freddy's comparative methylation levels.

Question 65

Lenny is a very active toddler who began to crawl, pull himself up to a standing position, walk, climb, and run at a very early age. Which statement is NOT an example of a way in which Lenny's phenotype may affect his environment?

A) Chasing Lenny and keeping him safe has made his parents very tired and stressed, resulting in a lack of patience with Lenny.
B) Lenny regularly seeks out new adventures, such as climbing to the top of his backyard swing set, in which he often gets injured and must be seen by a doctor.
C) In an attempt to get Lenny to use his high activity level in a constructive manner, his parents enroll him in a gymnastics class.
D) Lenny's father is also quite active, and he frequently brings Lenny to the playground, athletic games, and amusement parks.

Question 66

The twin-study design compares:

A) siblings who have lived together to those who have not.
B) same-sex twins to opposite-sex twins.
C) identical twins reared together to identical twins reared apart.
D) identical twins to fraternal twins.

Question 67

A study that examines whether adopted children's scores on a particular measure are more highly correlated with their adoptive parents' scores or their biological parents' scores is referred to as a(n) _____ study.

A) adoption
B) adoptive twin
C) twin
D) heritability

Question 68

Behaviour geneticists believe that _____ of the behavioural traits of human beings are influenced at least to some degree by genetic factors.

A) none
B) a small percentage
C) about half
D) all

Question 69

Behaviour genetics rests in part on the premise that, to the extent that environmental factors are important, individuals who _____ should be more similar than individuals who _____.

A) are closely related; are unrelated
B) are unrelated; are closely related
C) have lived together; have not lived together
D) have not lived together; have lived together

Question 70

A researcher finds that for a particular trait, first cousins are more similar than third cousins. This researcher has evidence that the trait is:

A) heritable.
B) polygenic.
C) multifactorial.
D) all of these.

Question 71

Traits that are influenced by a number of environmental and genetic factors are considered:

A) multifactorial.
B) heritable.
C) experience-dependent.
D) polygenetic.

Question 72

Genetic influence in behaviour genetics family studies is demonstrated by _____ correlations for higher degrees of _____ similarity.

A) higher; genetic
B) lower; genetic
C) higher; environmental
D) lower; environmental

Question 73

Traits that are influenced by genetic factors are considered:

A) multifactorial.
B) heritable.
C) sex-linked.
D) environmental.

Question 74

A twin study is conducted to examine the role of genetics and environment on the fondness of individuals for chocolate. Which result would lead to the conclusion that genetic factors are important in the development of this trait?

A) Twins who have lived together are more similar on the trait than twins who have lived apart.
B) Twins who have lived apart are more similar on the trait than twins who have lived together.
C) Identical twins are more similar on the trait than fraternal twins.
D) Fraternal twins are more similar on the trait than identical twins.

Question 75

Research at McGill University has revealed which of the following can have an epigenetic effect?

A) paternal care
B) maternal care
C) nutrition
D) inadequate exposure to light

Question 76

Which design would be ideal for studying behaviour genetics?

A) adoption study
B) family study
C) adoptive twin study
D) twin study

Question 77

Behaviour genetics rests in part on the premise that, to the extent that genetic factors are important, individuals who _____ should be more similar than individuals who _____.

A) are closely related; are unrelated
B) are unrelated; are closely related
C) have lived together; have not lived together
D) have not lived together; have lived together

Question 78

Gene expression can be suppressed by the process of:

A) methylation.
B) mutation.
C) recession.
D) myelination.

Question 79

A researcher finds that for a particular trait, the correlation between identical twins is greater than the correlation between nontwin siblings. This result demonstrates that:

A) environmental factors are important in the development of this trait.
B) genetic factors are important in the development of this trait.
C) genetic factors are not important in the development of this trait.
D) environmental factors are not important in the development of this trait.

Question 80

An adoptive twin study is conducted to examine the role of genetics and environment on sociability. Which result would lead to a conclusion that environmental factors are important in the development of this trait?

A) Identical twins reared together are more similar on the trait than identical twins reared apart.
B) Identical twins reared together are no more similar on the trait than identical twins reared apart.
C) Identical twins reared together are less similar on the trait than identical twins reared apart.
D) Identical twins reared apart are more similar on the trait than fraternal twins reared apart.