AP Biology Unit 5 Heredity

Define incomplete dominance.

• A form of inheritance where the heterozygous phenotype is an intermediate blend of the two homozygous phenotypes.

• A genetic condition where one allele completely masks the effect of another allele.

• A type of inheritance where both alleles are expressed equally in the phenotype.

• A situation where a single gene controls multiple traits.

What is the expected phenotype ratio in a monohybrid cross?

• 1:1

• 3:1

• 9:3:3:1

• 2:1

What is the probability of obtaining a red, axial offspring from a cross between a white, terminal flower and a red, axial flower?

• 1/4

• 3/8

• 9/16

• 1/2

What is codominance?

• A genetic scenario where one allele completely masks the effect of another allele.

• A genetic scenario where both alleles in a heterozygote are fully expressed, resulting in offspring with a phenotype that is neither dominant nor recessive.

• A genetic scenario where neither allele is expressed in the phenotype.

• A genetic scenario where one allele is dominant and the other is recessive.

What is the role of alleles in inheritance?

• Alleles are identical copies of a gene that do not affect traits.

• Alleles are different versions of a gene that determine specific traits in an organism.

• Alleles are proteins that help in the expression of genes.

• Alleles are environmental factors that influence genetic traits.

In an incomplete dominance cross between a white flower and a red flower, what is the probability of a pink offspring?

• 0%

• 50%

• 75%

• 100%

What is complete dominance in genetics?

• Complete dominance occurs when the phenotype of the heterozygote is the same as that of the homozygous dominant individual.

• Complete dominance occurs when both alleles are expressed equally in the phenotype.

• Complete dominance occurs when the phenotype of the homozygous recessive individual is expressed.

• Complete dominance occurs when one allele completely masks the effect of another allele.

How does the environment influence gene expression?

• Through genetic mutations that are inherited

• By affecting factors such as temperature, nutrition, and exposure to toxins

• By completely overriding genetic information

• Through random chance without any specific factors

What is the significance of the F1 generation in genetics?

• The F1 generation is the first filial generation, which is the result of a cross between two parental (P) generations.

• The F1 generation is the final generation in a genetic cross.

• The F1 generation is the generation that shows only recessive traits.

• The F1 generation is the generation that occurs after the F2 generation.

In a cross between two roan cows (codominant), what is the probability of a white cow?

• 1/4

• 1/2

• 3/4

• 0