Deck 7: Are You Only As Smart As Your Genes Mendelian and Quantitative Genetics

Question 1

What are the members of a pair of chromosomes (for example, the two copies of chromosome 1) called?

A) alleles
B) gametes
C) homologous chromosomes
D) sister chromatids

Answer 1

C

Question 2

What single, circular structure is found in prokaryotes such as bacteria?

Answer 2

chromosome

Question 3

During which process do gametes fuse together?

A) embryonic development
B) fertilization
C) meiosis
D) mitosis

Answer 3

B

Question 4

If the DNA contained in the chromosomes of an organism is similar to an instruction manual, then what are the genes "instructing" the cell to do?

A) grow in size until a certain point is reached, then reproduce itself
B) convert carbohydrates into enzymes
C) change shape and structure to meet the demands of the local environment
D) synthesize specific proteins from amino acids

Question 5

Half of the gametes produced by an organism with the genotype Aa will receive the A allele, while half will receive the a allele. What process produces such results?

A) independent assortment
B) mutation
C) random fertilization
D) segregation

Question 6

What is the correct sequence for the start of an organism's life cycle?

A) fertilization → meiosis → zygote → embryo
B) meiosis → fertilization → zygote → embryo
C) fertilization → zygote → meiosis → embryo
D) meiosis → fertilization → embryo → zygote

Question 7

Assuming that the genes are on separate chromosomes, an organism with the genotype AaBb will make gametes in the following proportions: 1/4 AB, 1/4 Ab, 1/4 aB, and 1/4 ab. What process produces such results?

A) independent assortment
B) mutation
C) random fertilization
D) segregation

Question 8

When does the segregation of alleles occur?

A) Homologous chromosomes separate during meiosis.
B) Homologous chromosomes separate during mitosis.
C) Sister chromatids separate during meiosis.
D) Sister chromatids separate during mitosis.

Question 9

What are the specialized cells used for sexual reproduction (for example, sperm cells)?

Question 10

What is a mistake that is made during copying of genetic information?

A) genotype
B) mutation
C) variance
D) zygote

Question 11

What causes the differences between two human cell types (for example, a skin cell and a brain cell)?

A) Different cell types begin with the same genes but eliminate certain genes as they develop.
B) Different cell types contain different genes.
C) Different cell types contain different proteins that give each cell a different function.
D) Different cell types contain the same genes but use different combinations of them.

Question 12

What are the segments of DNA that generally code for proteins?

Question 13

Which description applies to chromosomes?

A) Only eukaryotic cells contain chromosomes.
B) Chromosomes are made of carbohydrates.
C) Genes are found on chromosomes.
D) The most complex organisms have the largest number of chromosomes.

Question 14

What macromolecule is made from the instructions contained in a typical gene?

A) ATP
B) phospholipid
C) polysaccharide
D) protein

Question 15

When would monozygotic (identical) twins be produced?

A) One sperm fertilizes two different eggs.
B) One egg is fertilized by two different sperm.
C) One embryo splits into two embryos.
D) Two different sperm fertilize two different eggs.

Question 16

What are the alternate forms of a gene?

A) alleles
B) chromosomes
C) gametes
D) homologues

Question 17

How do the numbers of chromosomes differ for organisms?

A) Among all known living creatures, humans have the most chromosomes.
B) Animals have more chromosomes than plants.
C) Eukaryotes have more chromosomes than prokaryotes.
D) Prokaryotes have more chromosomes than fungi.

Question 18

What is the growth and reproduction of an individual called?

A) life cycle
B) genotype
C) phenotype
D) normal distribution

Question 19

What information can be inferred about genes that are located on different chromosomes?

A) These genes are inherited independently of each other.
B) Only the dominant alleles of these genes tend to be inherited together.
C) These genes are always inherited together.
D) These genes are more likely to undergo mutation.

Question 20

Which process creates new alleles to affect genetic diversity in a population?

A) independent assortment
B) random fertilization
C) segregation
D) mutation

Question 21

How many different types of offspring (genotypes) are possible as a result of this cross, according to the Punnett square in the diagram?

A) 1
B) 2
C) 3
D) 4

Question 22

What does a typical recessive allele code for?

A) a lethal protein
B) a nonfunctional protein
C) a functional protein
D) a mutant protein

Question 23

If you're interested in studying one gene within a human, and each gene has two alleles, then how many boxes would be used in the Punnett square to predict the inheritance of the alleles?

A) 2
B) 4
C) 8
D) 16

Question 24

Which genotype would have an advantage if a recessive allele changed cellular proteins that led to circulatory problems and premature death?

A) Any homozygous individual will always have an advantage over any heterozygous individual.
B) Any heterozygous individual will always have an advantage over any homozygous individual.
C) Any homozygous dominant individual will always have a disadvantage compared to any heterozygous individual.
D) Any heterozygous individual will have an advantage over any homozygous recessive individual.

Question 25

What may result if a mutation occurs in a gene?

A) There may be no effect on the protein encoded by the gene.
B) A nonfunctional protein may be created.
C) A protein with a new function will not be formed.
D) The phenotype of the organism may be changed.

Question 26

How did Gregor Mendel's research affect the science of his time?

A) His research was not appreciated by the scientific community until after he died.
B) His focus on pea plants showed that pea plants have very few heritable traits.
C) His results could predict heritability in plants but not animals.
D) His research included detailed studies on polygenic traits.

Question 27

When a recessive allele is associated with a genetic disease in humans, what would heterozygotes be considered?

A) vectors
B) dizygotic
C) carriers
D) qualitative

Question 28

If DNA is like an instruction manual, what would be similar to the typographical errors that may result when the DNA manual is transcribed?

A) dominant alleles
B) recessive alleles
C) mutations
D) homologous chromosomes

Question 29

When does a dominant genetic disorder occur?

A) Only one allele of the gene is the mutant allele.
B) Both alleles of the gene are the mutant allele.
C) Neither allele of the gene is the mutant allele.
D) Either one or both alleles of the gene are mutant.

Question 30

What are homologous chromosomes?

A) chromosome that almost always contain identical alleles
B) chromosomes that generally contain the same genes
C) chromosomes that are inherited together because they don't separate during meiosis
D) chromosomes that are fewer in body cells than in gametes

Question 31

Which structure would be expected in normal eye cells but not in normal heart cells?

A) the protein rhodopsin
B) light-detecting mitochondria
C) the protein troponin
D) genes for the production of rhodopsin

Question 32

What is CFTR/CFTR-DF508?

A) the dominant allele that causes cystic fibrosis
B) the recessive allele that causes cystic fibrosis
C) the homozygous genotype of a cystic fibrosis victim
D) the heterozygous genotype of a carrier of cystic fibrosis

Question 33

What percentage of alleles will be shared by certain siblings due to the law of independent assortment?

A) Monozygotic twins will have no alleles in common.
B) Monozygotic twins will have about 50% of their alleles in common.
C) Two typical siblings will have about 50% of their alleles in common.
D) Dizygotic twins will have 100% of their alleles in common.

Question 34

A heterozygous organism

A) always shows a recessive trait.
B) can't produce gametes.
C) has two identical alleles of a gene.
D) has two different alleles of a gene.

Question 35

Which situation most likely describes a recessive genetic disorder?

A) The mutant allele of the gene encodes a completely nonfunctional protein.
B) The mutant allele of the gene encodes a protein that has both the normal function and a new, harmful function.
C) The mutant allele of the gene encodes a protein that has a new, harmful function.
D) The mutant allele of the gene encodes a protein with the normal function but twice the normal activity.

Question 36

In a certain plant species, thick-shelled seeds are caused by the dominant allele T. Thin-shelled seeds are caused by the recessive allele t. What is the genotype of an individual with thin-shelled seeds?

A) TT
B) tt
C) Tt
D) tt or Tt

Question 37

What other term describes fraternal twins?

A) dizygotic
B) identical
C) monozygotic
D) heterozygous

Question 38

How many genetically different children could your parents have produced with their combinations of gametes?

A) 46
B) 285
C) 8 million
D) 64 trillion

Question 39

Cystic fibrosis is caused by the allele f, which is completely recessive to the normal dominant allele F. Consider a couple who both have the genotype Ff. What is the chance that their first child will develop cystic fibrosis?

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

Question 40

Cystic fibrosis is caused by the allele f, which is completely recessive to the normal dominant allele F. Consider a couple who both have the genotype Ff. What is the chance that their second child will develop cystic fibrosis?

A) 25%
B) 50%
C) 75%
D) 100%
E) It depends on which alleles were inherited by their first child.

Question 41

In pea plants, the allele for purple flowers (P) is dominant to the allele for white flowers (p). In a cross between a purple-flowered plant and a white-flowered plant, all 73 of the offspring plants had purple flowers. Which cross would provide such results?

A) pp × pp
B) Pp × Pp
C) PP × PP
D) PP × pp

Question 42

If a scientist is studying the heritability of IQ, which people would show the highest correlation between their IQ scores?

A) two unrelated children
B) a child and his mother
C) monozygotic twins
D) dizygotic twins

Question 43

Which trait is an example of a quantitative trait in humans?

A) cheek dimples
B) number of toe
C) musical ability
D) cystic fibrosis

Question 44

What term describes a trait that is controlled by many genes?

A) dihybrid
B) dominant
C) heritable
D) polygenic

Question 45

Which description applies to typical quantitative traits?

A) Such traits are easy to follow using Punnett squares.
B) Such traits are not affected by the environment.
C) Such traits are usually influenced by only one gene.
D) Such traits show continuous variation.

Question 46

Which cross shows both parents having two different alleles for each of two different genes?

A) AAbb × aaBB
B) aabb × AABB
C) AaBb × AaBb
D) AaBB × AABb

Question 47

What type of genetic cross involves two traits?

Question 48

What genotype would be found in an individual who is a carrier for a recessive genetic disorder but does not have symptoms of the disorder?

A) heterozygous
B) homozygous for the recessive allele
C) homozygous for the dominant allele
D) either homozygous for the recessive allele or heterozygous

Question 49

What term refers to the genetic makeup of an organism?

Question 50

What term refers to an individual who has two copies of the same allele?

Question 51

In a trait that shows continuous variation, what can we infer if the variance is low?

A) The majority of individuals will be far above the mean.
B) The majority of individuals will be very close to the mean.
C) The majority of individuals will be far below the mean.
D) Relatively few individuals will be very close to the mean.

Question 52

What was the purpose of the IQ test developed by Alfred Binet?

A) to measure intelligence based on the most accepted theory of the time
B) to compare the intelligence of different cultural subpopulations in the general population
C) to determine the relative effects of genes and environment on intelligence
D) to identify school children in need of remedial help

Question 53

What factor(s) typically influence a trait that shows continuous variation?

A) genetic factors only
B) environmental factors only
C) both genetic and environmental factors
D) neither genetic nor environmental factors

Question 54

Huntington's disease is caused by the allele H, which is completely dominant to the normal recessive allele h. Consider a couple where the man has the genotype Hh, and the woman has the genotype hh. What is the chance that their first child will develop Huntington's disease?

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

Question 55

What type of trait has an "off-or-on" character, where individuals have either one phenotype or another (for example, purple vs. white flowers)?

Question 56

Which situation demonstrates only the genetic influence on a trait?

A) Hair dye turns Angela's brown hair to red.
B) Sandy's hair becomes blonder when she spends time out in the sun.
C) Jen has brown hair, just like her mother and father.
D) Identical twins Kiera and Tanya have different colored hair.

Question 57

Which trait is an example of a qualitative trait in humans?

A) height
B) skin color
C) Huntington's disease
D) intelligence

Question 58

How many different kinds of gametes can be made by an individual with the genotype AaBb?

A) 2
B) 4
C) 8
D) 16

Question 59

In humans, straight thumbs are caused by the dominant allele T, while individuals who are tt have thumbs that curve backward ("hitchhiker's thumb"). Consider a family in which the father has straight thumbs, and both the mother and their only child have curved thumbs. What is the chance that their next child will have curved thumbs?

A) 25%
B) 50%
C) 75%
D) 100%

Question 60

What term refers to the physical traits of an organism?

Question 61

What type of trait shows continuous variation, where there is a large range of phenotypes in a population (for example, height or skin color)?

Question 62

Which pairs of people would provide the most useful information to geneticists, regarding the heritability of a certain trait?

A) non-twin siblings separated into different households soon after birth
B) monozygotic twins separated into different households soon after birth
C) non-twin siblings raised in the same household since birth
D) monozygotic twins raised in the same household since birth

Question 63

What is the estimated influence of genes (as opposed to environment) on a trait called?

Question 64

What type of a trait results in the large variation in shoe size among humans?

A) dizygotic
B) qualitative
C) quantitative
D) polygenic

Question 65

What conclusion can be made by the production of smarter than average children with doctorate-category sperm donations?

A) Because intelligence has no genetic basis, there's no real reason to expect children produced by this type of sperm to be smarter than average.
B) Children produced by this type of sperm have an approximately 72% chance of being more intelligent than average.
C) Children produced by this type of sperm will be smarter than average only if the mother has a high IQ.
D) There is currently no way to predict whether children produced by this type of sperm will be smarter than average.

Question 66

What conclusion was based on experiments with "maze-bright" and "maze-dull" rats?

A) An enriched environment increases maze-running ability only in dull rats.
B) A poor environment adversely affects maze-running ability in both bright and dull rats.
C) Maze-running ability is highly heritable and unaffected by environment.
D) Maze-running ability is based entirely on environment and unaffected by genes.

Question 67

What information can be inferred if the estimated heritability of a trait is approximately 0.50?

A) The environment must have little to no influence over the expression of the trait.
B) Genes exclusively control the expression of the trait in at least 50% of the population.
C) At least 50% of the variation in the trait in the population is due to genetic differences.
D) The environment completely controls the variation in the trait in the population.

Question 68

According to this graph, what can be concluded about immunity in these birds?

A) The heritability value is approximately 0.50.
B) Genes explain all the variation in immunity among birds in this population.
C) Environment still plays a role in these birds' immunity, even though heritability is high.
D) The heritability of immunity follows a bell-shaped curve, indicating a normal distribution.

Question 69

According to one study, the heritability of IQ score in humans has a value of 0.52. What does this tell us about the role of "nature" versus "nurture" in determining intelligence in humans?

A) Intelligence is a qualitative trait, affected by both genetics and the environment, and it can't be predicted by heritability scores.
B) Children of highly intelligent parents will likely be very intelligent, regardless of the environment in which they're raised.
C) There is an approximately equal chance that children of intelligent parents will be as intelligent as their parents, depending on the environment in which they're raised.
D) High heritability values don't mean that the intelligence of children can be accurately predicted because the environment plays a strong role.

Question 70

What does the highest point on a bell-shaped curve represent?

A) maximum amount of variation in a trait
B) heritability value of a trait
C) number of people in the population who are heterozygous
D) mean of the population

Question 71

What is represented by the difference between the lowest and highest values on the x-axis of a normal distribution curve for the population that is being studied?

A) bell-shaped curve
B) mean value
C) variance
D) frequency distribution