|
Of all the people who have studied inheritance, the person who made the most lasting impression on the science of genetics is
A. Charles Darwin.
B. Robert Hooke.
C. King George III.
D. Frederick Griffith.
E. Gregor Mendel.
|
E. Gregor Mendel.
|
|
If a healthy young couple are both carriers of cystic fibrosis, the chance that each of their future children will inherit this serious illness is
A. 0%, because cystic fibrosis is not an inherited illness.
B. 25%.
C. 10%.
D. 50%.
E. 100%.
|
B. 25%
|
|
A portion of DNA that encodes a specific protein is
A. a gene.
B. a chromosome.
C. a chromatid.
D. a centromere.
E. a kinetochore.
|
A. a gene.
|
|
Alternate forms of the same gene are called
A. chromatids.
B. centromeres.
C. chromosomes.
D. alleles.
E. traits.
|
D. alleles.
|
|
In humans, alleles are inherited from
A. females only (mothers).
B. males only (fathers).
C. males and females (one allele from each parent).
D. males and females (two alleles from each parent).
E. None of the answers are correct.
|
D. males and females (two alleles from each parent).
|
|
All gametes contain
A. two identical sets of chromosomes.
B. two different sets of chromosomes.
C. one set of chromosomes.
D. one chromosome.
E. two chromosomes.
|
C. one set of chromosomes.
|
|
The pea plant (Pisum sativum) is a good choice for studying heredity because it
A. develops slowly.
B. produces only a few offspring.
C. is easy to control which plants mate with each other.
D. has only a few traits that appear in two easily distinguishable forms.
E. All answers are correct.
|
C. is easy to control which plants mate with each other.
|
|
Mendel called a masking trait
A. dominant.
B. recessive.
C. homologous.
D. homozygous.
E. heterozygous.
|
A. dominant.
|
|
Mendel called a trait that is masked
A. homozygous.
B. heterozygous.
C. dominant.
D. recessive.
E. None of the answers are correct.
|
D. recessive.
|
|
An allele that exerts its effects whenever it is present is
A. recessive.
B. dominant.
C. homologous.
D. homozygous.
E. heterozygous.
|
B. dominant.
|
|
If the two alleles for a particular gene are identical the gene pair is
A. homozygous.
B. homologous.
C. heterozygous.
D. dominant.
E. recessive.
|
A. homozygous.
|
|
If the two alleles for a particular gene are different the gene pair is
A. homologous.
B. heterozygous.
C. homozygous.
D. dominant.
E. recessive.
|
B. heterozygous.
|
|
If an individual is heterozygous for a particular trait
A. each parent contributed a different allele for that trait.
B. each parent contributed the same allele for that trait.
C. one parent contributed two different alleles for that trait.
D. one parent contributed two copies of the same allele for that trait.
E. a mutation must have occurred.
|
A. each parent contributed a different allele for that trait.
|
|
If an individual is homozygous for a particular trait
A. each parent contributed a different allele for that trait.
B. one parent contributed two different alleles for that trait.
C. each parent contributed the same allele for that trait.
D. one parent contributed two copies of the same allele for that trait.
E. a mutation must have occurred.
|
C. each parent contributed the same allele for that trait.
|
|
Recessive alleles seem to vanish in some generations and reappear in later ones due to
A. they cannot be expressed in males.
B. they are masked by a dominant allele.
C. they cannot be expressed in females.
D. they cannot be expressed in successive generations.
E. they are lost by mutation.
|
B. they are masked by a dominant allele.
|
|
Genotype means
A. the number of gametes in an individual.
B. the combination of alleles in an individual.
C. the number of chromosomes in an individual.
D. the observable expression of the genes in an individual.
E. the genes an individual has.
|
B. the combination of alleles in an individual.
|
|
Phenotype means
A. the number of gametes in an individual.
B. the number of chromosomes in an individual.
C. the combination of alleles in an individual.
D. the genes an individual has.
E. the observable expression of the genes in an individual.
|
E. the observable expression of the genes in an individual.
|
|
The most common or "normal" phenotype or allele for a gene in a population is the
A. the wild type.
B. the dominant population.
C. the recessive population.
D. the P generation.
E. the F1 generation.
|
A. the wild type.
|
|
In the study of genetics the offspring of the P generation is referred to as the
A. wild type generation.
B. F1 generation.
C. genotype.
D. F2 generation.
E. phenotype.
|
B. F1 generation.
|
|
A pea plant with (Tt) as its genotype should be referred to as
A. the wild type.
B. homozygous dominant.
C. heterozygous.
D. homozygous recessive.
E. mutant.
|
C. heterozygous.
|
|
A monohybrid cross is a mating between two individuals that are both
A. homozygous for one gene.
B. heterozygous for two genes.
C. homozygous for two genes.
D. heterozygous for one gene.
E. None of the answers are correct.
|
D. heterozygous for one gene.
|
|
Any monohybrid cross consisting of one dominant and one recessive allele for the trait studied should result in a ratio of ______________ dominant to __________________ recessive.
A. three; one
B. one; one
C. one; two
D. two; one
E. one; three
|
A. three; one
|
|
A test cross is a mating of an individual with an unknown genotype and an individual that
A. is heterozygous.
B. is homozygous dominant.
C. is homozygous recessive.
D. has any known genotype.
E. is the wild type
|
C. is homozygous recessive.
|
|
Two alleles of each gene are packaged into separate gametes and they move apart from each other during gamete formation summarizes Mendel’s
A. law of segregation.
B. law of random fertilization.
C. law of population dynamics.
D. law of crossing over.
E. law of independent assortment.
|
A. law of segregation.
|
|
A dihybrid cross is a mating between two individuals that are each ______________ for ___________ gene (genes).
A. homozygous, one
B. homozygous, two
C. homologous, two
D. heterozygous, one
E. heterozygous, two
|
E. heterozygous, two
|
|
Segregation of alleles for a gene on one chromosome that does not influence the segregation of alleles for a gene on another chromosome during meiosis is Mendel’s
A. law of independent assortment.
B. law of random fertilization.
C. law of population dynamics.
D. law of crossing over.
E. law of segregation.
|
A. law of independent assortment.
|
|
In the ABO blood type system the alleles IA, IB and i produce
A. three phenotypes.
B. two phenotypes.
C. one phenotype.
D. four phenotypes.
E. type A and type B blood types only.
|
D. four phenotypes.
|
|
In the ABO blood type system, the IA allele is _____ with the IB allele.
A. dominant
B. codominant
C. recessive
D. homologous
E. heterologous
|
B. codominant
|
|
If the heterozygous phenotype is intermediate between the homozygotes, this is called
A. codominance.
B. independent assortment.
C. linkage.
D. incomplete dominance.
E. polygenic.
|
D. incomplete dominance.
|
|
A gene that produces a protein important in more than one biochemical pathway is
A. dominant.
B. recessive.
C. pleiotropic.
D. codominant.
E. incomplete dominant.
|
C. pleiotropic.
|
|
Autosomes
A. are chromosomes that are the same for both sexes.
B. include the Y chromosome in humans.
C. include the X chromosome in humans.
D. are the sex chromosomes.
E. All answers are correct.
|
A. are chromosomes that are the same for both sexes.
|
|
Linked genes, by definition, are genes that
A. are found on the same chromosome.
B. have no alleles.
C. are found in the same species.
D. have more alleles than usual.
E. are alleles that are found in different daughter cells.
|
A. are found on the same chromosome.
|
|
Crossing over is more likely to separate genes on a chromosome if they are
A. close together.
B. far apart.
C. recessive genes.
D. dominant genes.
E. mutated genes.
|
B. far apart
|
|
Diagrams of gene order and spacing on chromosomes are
A. genotypes and phenotypes.
B. phenotypes.
C. linkage maps.
D. genotypes.
E. metabolic maps.
|
C. linkage maps.
|
|
To inherit an autosomal dominant disorder a person could receive the disease causing allele from
A. the father only, not the mother.
B. the mother only, not the father.
C. the mother or the father.
D. the parent who does not exhibit the disease.
E. All answers are correct.
|
C. the mother or the father.
|
|
To inherit an autosomal recessive disorder requires the person receive the disease causing allele from
A. the father only.
B. the mother only.
C. only the parent having the disease.
D. only one parent who is homozygous recessive for the disease.
E. both parents.
|
E. both parents.
|
|
A person has a recessive allele for a disease but the allele is masked by the presence of a normal dominant allele in the person. This person
A. is homozygous for the disease.
B. cannot produce gametes.
C. is termed a carrier.
D. is termed a linkage group.
E. has the disease but cannot pass this disease to their offspring.
|
C. is termed a carrier.
|
|
Diagrams depicting family relationships and phenotypes for a genetic disorder are
A. linkage maps.
B. pedigree charts.
C. genotype maps.
D. Punnett squares.
E. bell-shaped curves.
|
B. pedigree charts.
|
|
The chromosome that determines human gender is
A. the X chromosome.
B. chromosome number 21.
C. the group of autosomes known as the SRY group.
D. chromosome number 22.
E. the Y chromosome.
|
E. the Y chromosome.
|
|
Hemophilia A is caused by
A. an X-linked recessive disorder causing a defective blood clotting protein.
B. an Y-linked recessive disorder.
C. a defective neuron response.
D. an X-linked dominant disorder causing a defective blood clotting protein.
E. an X-linked dominant disorder.
|
A. an X-linked recessive disorder causing a defective blood clotting protein.
|
|
If a diploid cell has 14 chromosomes, it will have
A. 14 pairs of homologous chromosomes.
B. 7 pairs of homologous chromatids.
C. 14 pairs of homologous chromatids.
D. 7 pairs of homologous chromosomes.
E. 14 alleles.
|
D. 7 pairs of homologous chromosomes.
|
|
Homologous chromosomes have
A. the same genes but can have different alleles.
B. the same genes and alleles.
C. different genes and alleles.
D. different genes, but can have the same alleles.
|
A. the same genes but can have different alleles.
|
|
A single chromosome has
A. multiple genes each with a single allele.
B. multiple genes each with multiple alleles.
C. a single gene with a single allele.
D. a single gene with multiple alleles.
|
A. multiple genes each with a single allele.
|
|
Yellow peas are an example of
A. a phenotype.
B. a genotype.
C. an allele.
D. a gene.
E. a loci.
|
A. a phenotype.
|
|
Having the alleles Tt is
A. a phenotype.
B. linkage.
C. a genotype.
D. a gene.
E. a loci.
|
C. a genotype.
|
|
If a pea plant is heterozygous for yellow seeds (Yy), which gametes will it produce?
A. Y only
B. Y or y
C. y only
D. Yy
E. YYyy
|
B. Y or y
|
|
If a pea plant is homozygous recessive for yellow seeds (yy), which gametes will it produce?
A. Y only
B. y only
C. Yy
D. YYyy
E. Y or y
|
B. y only
|
|
If a pea plant is homozygous for yellow seeds (YY), which gametes will it produce?
A. Y only
B. Y or y
C. y only
D. Yy
E. YYyy
|
A. Y only
|
|
If you cross two heterozygous (Yy) pea plants, what proportion of the offspring will be heterozygous?
A. 25%
B. 75%
C. 50%
D. 0%
E. 100%
|
C. 50%
|
|
If you cross two heterozygous Yy pea plants, what proportion of the offspring will be the dominant color yellow?
A. 50%
B. 75%
C. 25%
D. 0%
E. 100%
|
B. 75%
|
|
Which gametes can a RrYy plant produce?
A. Rr or Yy
B. RY or ry
C. RrYy
D. RY, Ry, rY, or ry
E. R or r
|
D. RY, Ry, rY, or ry
|
|
Which gametes can a RRyy plant produce?
A. RR or yy
B. Ry
C. RY or ry
D. RRyy
E. R or y
|
B. Ry
|
|
In an inherited form of high cholesterol, (HH) individuals have a blood cholesterol level greater than 500mg/dL, (RH) individuals are near 300mg/dL, and normal (RR) cholesterol levels should be less than 200mg/dL. The H allele is ___ to the R allele.
A. codominant
B. dominant
C. recessive
D. homozygous
E. incompletely dominant
|
E. incompletely dominant
|
|
In cystic fibrosis, two unaffected carriers can have a child with the disease. It is as common in boys as in girls. This disease is
A. autosomal dominant.
B. X-linked recessive.
C. autosomal recessive.
D. X-linked dominant.
E. pleiotropic.
|
C. autosomal recessive.
|
|
The wide variation in skin color in humans is best explained by
A. Skin color is a polygenic trait.
B. Skin color is influenced by environmental changes like improvements in diet.
C. Skin color is influenced by an X-linked gene.
D. Skin color is influenced by a Y-linked gene.
E. Skin color is influenced by crossing over
|
A. Skin color is a polygenic trait.
|
|
Which has the following in order from smallest to largest
A. DNA nucleotides, gene, chromosome, cell
B. gene, chromosome, DNA nucleotides, cell
C. DNA nucleotides, chromosome, gene, cell
D. DNA nucleotides, chromosome, cell, gene
E. gene, DNA nucleotides, chromosome, cell
|
A. DNA nucleotides, gene, chromosome, cell
|
|
Which of the following is in the correct order?
A. meiosis of diploid cell, haploid gametes produced, fertilization, new diploid organism formed
B. haploid gametes produced, fertilization, meiosis of diploid cell, new diploid organism formed
C. fertilization, haploid gametes produced, new diploid organism formed, meiosis of diploid cell
D. meiosis of diploid cell, new diploid organism formed, haploid gametes produced, fertilization
E. haploid gametes produced, new diploid organism formed, fertilization, meiosis of diploid cell
|
A. meiosis of diploid cell, haploid gametes produced, fertilization, new diploid organism formed
|
