INHERITANCE

Red-flowered snapdragons are crossed with white-flowered snapdragons, producing all pink snapdragons in the F1 generation. What would you expect if you crossed pink with pink? ....... red,.......... pink,.......... white.

1/4 1/2 1/4

A student analyzed ears of corn that demonstrated two traits in the F2 kernels, purple or white colors and smooth or wrinkled shapes. A tabulation of 135 individual kernels gave the following results: purple and smooth = 75 white and smooth = 28 purple and wrinkled = 24 white and wrinkled = 8 How many phenotypes are present?

4

The phenotypic ratio for the F2 generation in a dihybrid cross will theoretically be _____.

9:3:3:1

A cross involving purebred, red snapdragons and purebred, white snapdragons produce all pink offspring because both genes are present, neither being............ over the other, resulting in the........... of the trait.

Dominant Blending

In a dihybrid cross, the F2 will have nine genotypes, but only four phenotypes because the........ genes cause the traits to mask the traits.

Heterozygous Dominant Recessive

When the blending of traits occurs, it is referred to as the principle of _____.

Incomplete dominance

If one parent is heterozygous white (Ww) and the other is homozygous black (ww), give the phenotype and genotype ratios for this cross.

Phenotype: 1/2 black, 1/2 white Genotype: 1:1

A student analyzed ears of corn that demonstrated two traits in the F2 kernels, purple or white colors and smooth or wrinkled shapes. A tabulation of 135 individual kernels gave the following results: purple and smooth = 75 white and smooth = 28 purple and wrinkled = 24 white and wrinkled = 8 The............ alleles are dominant.

Purple and smooth

A student analyzed ears of corn that demonstrated two traits in the F2 kernels, purple or white colors and smooth or wrinkled shapes. A tabulation of 135 individual kernels gave the following results: purple and smooth = 75 white and smooth = 28 purple and wrinkled = 24 white and wrinkled = 8 What would be the only phenotype present in the F1 generation?

Purple and smooth

While conducting experiments on pea plants, Mendel observed that the combination of traits in the offspring did not match up with the parents. How did Mendel explain this?

The Principle of Independent Assortment

Punnett square

a grid system used to predict possible combinations of genes due to random fertilization

Multiple alleles _____.

can interact to influence a trait, such as eye color

A red flower and a white flower produce pink offspring. What condition explains this phenomenon?

co-dominance

codominance

condition in heterozygotes in which both members of an allelic pair are dominant and both contribute to the phenotype

incomplete dominance

condition in heterozygotes in which both members of an allelic pair are neither dominant nor recessive to other alleles, so the two traits blend in the phenotype of the individual

carrier

condition of being heterozygous for a recessive trait

Traits that are sex-linked are carried on _____.

either the X or Y chromosome

sex-linked

genes that are located in the sex chromosome

multiple alleles

when more than two alternatives for a gene exist