Question

genetics and heredity exam
select two statements that are true about dominant and recessive traits.
☑ a dominant allele will always be expressed when it is present in an organisms genotype
☐ a recessive trait is less common in a population because it is weaker than a dominant trait.
☐ an individual can carry a recessive allele without showing the recessive trait.
☐ if both parents show a dominant trait, all of their children will always show the dominant trait.

Explanation:

1. For the first true statement: Dominant alleles mask recessive ones, so their trait is expressed whenever present in the genotype.
2. For the second true statement: Individuals can be heterozygous (have one dominant and one recessive allele), where the dominant trait is expressed, hiding the recessive allele they carry.
3. Incorrect statements: Recessive traits are not "weaker"—their frequency depends on population genetics, not trait strength. Dominant trait parents can both be heterozygous, leading to a 25% chance of a child with the recessive trait.

Answer:

• A dominant allele will always be expressed when it is present in an organism's genotype.
• An individual can carry a recessive allele without showing the recessive trait.