BIOLOGY: Campbell's Chapter 15: Beyond Mendelian Genetics

A man with hemophilia (a recessive, sex-linked condition) has a daughter of normal phenotype. She marries a man who is normal for the trait. What is the probability that a daughter of this mating will be a hemophiliac?

0

A man with hemophilia (a recessive, sex-linked condition) has a daughter of normal phenotype. She marries a man who is normal for the trait. What is the probability that a son will be a hemophiliac?

1/2

Red-green color blindness is due to an X-linked recessive allele in humans. A widow's peak (a hairline that comes to a peak in the middle of the forehead) is due to an autosomal dominant allele. Consider the following family history: A man with a widow's peak and normal color vision marries a color-blind woman with a straight hairline. The man's father had a straight hairline, as did both of the woman's parents. If the couple has a child, what is the chance that it will be a son with a widow's peak? What is the chance that any son the couple has will be color blind with a straight hairline? What is the chance that any daughter that the couple has will be color blind with a widow's peak? Suppose the couple had a daughter with normal color vision and a widow's peak. What is the chance that she is heterozygous for both genes?

1/4 1/2 0 1

If a diploid cell undergoes meiosis and produces two gametes with n + 1 chromosomes and two gametes with n− 1 chromosomes, what type of error occurred? A nondisjunction error occurred in meiosis I, in which both members of all homologous pairs migrated to the same pole of the cell. A nondisjunction error occurred in meiosis I, in which both members of a homologous pair migrated to the same pole of the cell. No error occurred; these are normal gametes. A nondisjunction error occurred in meiosis II, in which both sister chromatids of a chromosome migrated to the same pole of the cell.

A nondisjunction error occurred in meiosis I, in which both members of a homologous pair migrated to the same pole of the cell.

If a diploid cell undergoes meiosis and produces two gametes that are normal, and one with n − 1 chromosomes, and one with n + 1 chromosomes, what type of error occurred? A nondisjunction error occurred in meiosis II, in which both sister chromatids of a chromosome migrated to the same pole of the cell. No error occurred; these are normal gametes. A nondisjunction error occurred in meiosis I, in which both members of a homologous pair migrated to the same pole of the cell. A nondisjunction error occurred in meiosis I, in which both members of all homologous pairs migrated to the same pole of the cell.

A nondisjunction error occurred in meiosis II, in which both sister chromatids of a chromosome migrated to the same pole of the cell.

Imagine a human disorder that is inherited as a dominant, X-linked trait. How would the frequency of this disorder vary between males and females? Males and females would display this disorder with equal frequency. Females would display this disorder with greater frequency than males. Males would display this disorder with greater frequency than females.

Females would display this disorder with greater frequency than males

Gregor Mendel set up a dihybrid cross with one pea plant from the parental generation (P) producing round yellow peas and the other pea plant producing wrinkled green peas. The F2 generation included 315 plants producing round yellow peas, 108 with round green peas, 101 with wrinkled yellow peas, and 32 with wrinkled green peas. How would these results have differed if pea shape and pea color had been linked genes, located close together on the same chromosome? The F2 generation would have included a higher percentage of pea plants producing yellow peas. The F2 generation would have included a lower percentage of pea plants producing wrinkled, green peas. The F2 generation would have included a higher percentage of pea plants producing round, yellow peas.

The F2 generatin would have included a higher percentage of pea plants producing round, yellow peas

Which of these descriptions of the behavior of chromosomes during meiosis explains Mendel's law of independent assortment? The two alleles for each gene separate as homologous chromosomes move apart during anaphase I. The arrangement of each pair of homologous chromosomes on the metaphase plate during metaphase I is random with respect to the arrangements of other pairs. Sister chromatids separate during anaphase II.

The arrangement of each pair of homologous chromosomes on the metaphase plate during metaphase I is random with random with respect to the arrangements of other pairs

Which of these descriptions of the behavior of chromosomes during meiosis explains Mendel's law of segregation? Sister chromatids separate during anaphase II. The two alleles for each gene separate as homologous chromosomes move apart during anaphase I. The arrangement of each pair of homologous chromosomes on the metaphase plate during metaphase I is random with respect to the arrangements of other pairs.

The two alleles for each gene separate as homologous chromosomes move apart during anaphase I

Of the following chromosomal abnormalities, which type is most likely to be viable in humans? Trisomy Triploidy Monosomy Haploidy

Trisomy

Which syndrome is characterized by the XO chromosome abnormality? Trisomy X Klinefelter syndrome Down syndrome Turner syndrome

Turner syndrome

Bob has a genetic condition that affects his skin. Bob's wife, Eleanor, has normal skin. No one in Eleanor's family has ever had the skin condition. Bob and Eleanor have a large family. Of their eleven children, all six of their sons have normal skin, but all five of their daughters have the same skin condition as Bob. Based on Bob and Eleanor's family history, what inheritance pattern does the skin condition most likely follow? autosomal dominant Y-linked autosomal recessive X-linked dominant X-linked recessive

X-linked dominant

With all possible combinations the F1 generation makes gametes with the following genotypes ________

YR, Yr, yR, yr

The resulting offspring between YYRR and yyrr will have the genotype ______

YyRr

What kind of cell results when a diploid and a haploid gamete fuse during fertilization? A monoploid cell A trisomic cell A triploid cell A monosomic cell

a triploid cell

According to Mendel's law of independent assortment, the alleles for seed color and seed shape are transmitted into gametes in _______

all possible combinations

n nondisjunction occur? Choose the best answer. All three answers are correct. In mitosis, when sister chromatids fail to separate In meiosis, when sister chromatids fail to separate In meiosis, when homologous chromosomes fail to separate

all three answers are correct

What is a nondisjunction? An error in which a diploid cell or organism lacks a chromosome of one type, producing a chromosome number of 2n - 1 An error in which a diploid cell or organism has an extra chromosome of one type, producing a chromosome number of 2n + 1 An error in cell division that causes homologous chromosomes or sister chromatids to move to the same side of the dividing cell None of the above

an error in cell division that causes homologous chromosoems or sister chromatids to move to the same side of the dividing cell

Alleles Assortment for Seed Color and Seed Shape Y may sort with R or r; y may sor with R or r four phenotypes produced in F2 generation in 9:3:3:1 ratio each cell has the genotype YyRr four types of gametes produced: YR, Yr, yR and yr

each cell has the genotype YyRr Y may sort with R or r; y may sort with R or r four types of gametes produced: YR, Yr, yR and yr four phenotypes produced in F2 generation in 9:3:3:1

At fertilization, two gametes (egg and sperm) come together. The resulting F2 generation exhibits _____ different phenotypes in the ration of _______

four.... 9:3:3:1

Phases of meiosis/fertilization fertilization anaphase I telophase II metaphase I

metaphase I anaphase I telophase II fertilization

Chromosome Behavior sister chromatids have separated chromosomes in haploid gametes combine in diploid zygote two chromosome arrangements equally probable at metaphase plate homologous chromosomes separate

two chromosome arrangements equally probable at metaphase plate homologous chromosomes separate sister chromatids have separated chromosomes in haploid gametes combine in diploid gametes

In the P generation, a true breeding pea plant with genotype YYRR is crossed with a true breeding plant with genotype _____

yyrr