Use the Figure and the Following Description to Answer the Question.
Use the figure and the following description to answer the question.
In a particular plant, leaf colour is controlled by gene locus D. Plants with at least one allele D have dark green leaves, and plants with the homozygous recessive dd genotype have light green leaves. A true-breeding, dark-leafed plant is crossed with a light-leafed one, and the F1 offspring is allowed to self-pollinate. The predicted outcome of the F2 is diagrammed in the Punnett square shown in the figure, where 1, 2, 3 and 4 represent the genotypes corresponding to each box within the square.
Which of the boxes marked 1-4 correspond to plants that will be true-breeding?
A) 1 and 4 only
B) 2 and 3 only
C) 1, 2, 3 and 4
D) 1 only
Skin colour in a certain species of fish is inherited by a single gene with four different alleles. How many different types of gametes would be possible in this organism?
Why did all of the F1 offspring of Mendel's classic pea cross always look like one of the two parental varieties?
A) No genes interacted to produce the parental phenotype.
B) Each allele affected phenotypic expression.
C) The traits blended together during fertilisation.
D) One allele was dominant.
Mendel crossed yellow-seeded and green-seeded pea plants and then allowed the offspring to self-pollinate to produce an F2 generation. The results were as follows: 6,022 yellow and 2,001 green (8,023 total). Which of the following statements correctly describes the relationship of the allele for green seeds to the allele for yellow seeds?
A) The green allele is dominant to the yellow allele.
B) The two alleles exhibit incomplete dominance.
C) The green allele is recessive to the yellow allele.
D) The two alleles are codominant.