quiz 8

If roan cattle (incomplete dominance) are allowed to breed, what ratio of phenotypes is expected in the offspring? Question 2 options: 1:1 red:white all roan 1:2:1 red:roan:white 3:1 red:white 1:1:1 red:roan:white

1:2:1 red:roan:white

Imagine a locus with four different alleles for fur color in an animal. The alleles are named Da, Db, Dc, and Dd. If you crossed two heterozygotes, DaDb and DcDd, what genotype proportions would you expect in the offspring? Question 10 options: 25% DaDc, 25% DaDd, 25% DbDc, 25% DbDd 50% DaDb, 50% DcDd 25% DaDa, 25% DbDb, 25% DcDc, 25% DdDdDcDd 50% DaDc, 50% DbDd 25% DaDb, 25% DcDd, 25% DcDc, 25% DdDd

25% DaDc, 25% DaDd, 25% DbDc, 25% DbDd

ABO blood type in humans exhibits codominance and multiple alleles. O is a result of being homozygous recessive. What is the likelihood of a type A father and a type A mother having a type O child? Question 5 options: It is impossible. 25% if both parents are heterozygous 50% if both parent are heterozygous 25% if only the father is heterozygous 25% if only the mother is heterozygous

25% if both parents are heterozygous

Which of the following statements is true? Question 1 options: Populations only contain 2 alleles for a given gene. Variants (mutations) are always recessive. A test cross always uses a homozygous recessive individual. Punnett squares contain a maximum of 4 squares.

A test cross always uses a homozygous recessive individual.

When inheritance for a particular characteristic depends on the combined effects of numerous genes, it is due to ____________. Question 9 options: Polygenic inheritance Linked genes Traditional Mendelian genetics A test cross

Polygenic inheritance

The following offspring were observed from many crossings of the same pea plants. What genotypes were the parents? 465 purple axial flowers 140 white axial flowers 152 purple terminal flowers 53 white terminal flowers Question 6 options: PpAa x PpAA PpAa x ppAA PPAA x ppaa PpAa x PpAa PPaa x ppAA

PpAa x PpAa

In cats, a sex-linked gene affects coat color. The O allele produces an enzyme that converts eumelanin, a black or brown pigment, into phaeomelanin, an orange pigment. The o allele is recessive to O and produces a defective enzyme, one that does not convert eumelanin into phaeomelanin. Which of the following statements is/are accurate? Question 7 options: The phenotype of o-Y males is black/brown because the nonfunctional allele o does not convert eumelanin into phaeomelanin. The phenotype of OO and Oo males is orange because the functional allele O converts eumelanin into phaeomelanin. The phenotype of Oo males is mixed orange and black/brown because the functional allele O converts eumelanin into phaeomelanin in some cell groups (orange) and because in other cell groups the nonfunctional allele o does not convert eumelanin into phaeomelanin. The phenotype of O-Y males is orange because the nonfunctional allele O does not convert eumelanin into phaeomelanin, while the phenotype of o-Y males is black/brown because the functional allele o converts eumelanin into phaeomelanin.

The phenotype of o-Y males is black/brown because the nonfunctional allele o does not convert eumelanin into phaeomelanin.

A cross between homozygous purple-flowered and homozygous white-flowered pea plants results in offspring with purple flowers. This demonstrates Question 3 options: the blending model of genetics. incomplete dominance. complete dominance. a dihybrid cross. the mistakes made by Mendel.

complete dominance.

A pea plant is heterozygous at the independent loci for flower color (white versus purple) and seed color (yellow versus green). What types of gametes can it produce? Question 4 options: two gamete types: white/white and purple/purple two gamete types: white/yellow and purple/green four gamete types: white/yellow, white/green, purple/yellow, and purple/green four gamete types: white/purple, yellow/green, white/white, and purple/purple one gamete type: white/purple/yellow/green

four gamete types: white/yellow, white/green, purple/yellow, and purple/green

Pea plants were particularly well suited for use in Mendel's breeding experiments for all of the following reasons except that... Question 8 options: peas show easily observed variations in a number of characters, such as pea shape and flower color. it is possible to control matings between different pea plants. it is possible to obtain large numbers of progeny from any given cross. peas have an unusually long generation time. many of the observable characters that vary in pea plants are controlled by single genes.

peas have an unusually long generation time.