Dominant & Recessive

What is a Punnett square?

• A diagram used to predict the genetic outcomes of a cross between two organisms.

• A tool for measuring the height of plants.

• A method for calculating the age of fossils.

• A chart for organizing different species of animals.

What is a dominant phenotype?

• A trait that is only expressed when two recessive alleles are present.

• The observable trait that is expressed when at least one dominant allele is present in the genotype.

• A trait that is always expressed regardless of the alleles present.

• A phenotype that cannot be observed in the organism.

What is a recessive phenotype?

• A trait that is always expressed in the phenotype regardless of the genotype.

• A trait that is expressed only when two recessive alleles are present in the genotype.

• A trait that can be expressed with just one dominant allele in the genotype.

• A trait that is never expressed in the phenotype.

What is an allele?

• A type of chromosome that determines physical traits.

• A variant form of a gene that can produce different traits.

• A process of cell division that leads to genetic variation.

• A structure that carries genetic information in the form of DNA.

What is the principle of dominance?

• The principle of dominance states that in a heterozygous genotype, the dominant allele will mask the effect of the recessive allele.

• The principle of dominance states that recessive alleles are always expressed in the phenotype.

• The principle of dominance states that alleles are always inherited in pairs from each parent.

• The principle of dominance states that dominant alleles can never be masked by recessive alleles.

What does the genotype 'BB' represent?

• A homozygous recessive condition, meaning both alleles are recessive.

• A heterozygous condition, meaning one allele is dominant and one is recessive.

• A homozygous dominant condition, meaning both alleles are dominant.

• A condition where one allele is absent.

What is the phenotype of the genotype 'DD'?

• Recessive

• Dominant

• Incomplete dominance

• Codominance

What is the difference between homozygous and heterozygous genotypes?

• Homozygous genotypes have two identical alleles (e.g., 'BB' or 'bb'), while heterozygous genotypes have one dominant and one recessive allele (e.g., 'Bb').

• Homozygous genotypes have one dominant and one recessive allele (e.g., 'Bb'), while heterozygous genotypes have two identical alleles (e.g., 'BB' or 'bb').

• Homozygous genotypes have two different alleles (e.g., 'Bb'), while heterozygous genotypes have two identical alleles (e.g., 'AA').

• Homozygous genotypes can only be dominant, while heterozygous genotypes can be either dominant or recessive.

How can you determine if a trait is dominant or recessive?

• By observing the phenotypes of offspring in genetic crosses.

• By analyzing the DNA sequence of the parents.

• By measuring the height of the plants only.

• By counting the number of offspring produced.

What does it mean if a trait is said to be 'inherited'?

• It means the trait is acquired through environmental factors.

• It means the trait is passed from parents to offspring through genes.

• It means the trait is only present in one generation.

• It means the trait can change with each generation.