Alleles, Genes, & Traits

What is a dominant allele?

• An allele that is masked by a recessive allele

• An allele that expresses its trait even when only one copy is present

• An allele that only expresses its trait when two copies are present

• An allele that is always inherited from the mother

Which of the following is a characteristic of a recessive allele?

• It is always expressed in the phenotype

• It is masked by a dominant allele

• It is stronger than a dominant allele

• It is only found in purebred organisms

What does it mean if an organism is hybrid for a trait?

• It has two identical alleles for a trait

• It has two different alleles for a trait

• It has no alleles for a trait

• It has more than two alleles for a trait

What is a purebred organism?

• An organism with two different alleles for a trait

• An organism with two identical alleles for a trait

• An organism with no alleles for a trait

• An organism with more than two alleles for a trait

How can genetic traits be analyzed?

• By observing the environment only

• By studying the alleles and their combinations

• By ignoring the genetic makeup

• By looking at the organism's diet

Which of the following best describes the relationship between genes and the environment?

• Genes are not influenced by the environment

• The environment can influence the expression of genes

• Genes determine the environment

• The environment and genes are unrelated

If a plant has alleles Tt for height, where T is tall and t is short, what would the plant look like?

• Short

• Medium

• Tall

• Cannot be determined

Which of the following is an example of a trait influenced by both genes and the environment?

• Eye color

• Blood type

• Height

• Number of fingers

If an organism has alleles BB for a trait, what can be said about it?

• It is hybrid

• It is purebred

• It has no alleles

• It is recessive

How do environmental factors influence acquired traits?

• Environmental factors such as culture, education, and personal experiences shape acquired traits.

• Acquired traits are solely determined by genetic factors and are not influenced by the environment.

• Environmental factors have no impact on acquired traits; they are fixed at birth.

• Acquired traits are influenced by environmental factors only during childhood.