Question

Which of the following represents the most likely genotypes of the parents in the given cross?

Question options:
a) Both parents are homozygous dominant.
b) Both parents are heterozygous.
c) The parent with small flowers is homozygous recessive, and the parent with large flowers is homozygous dominant.
d) The parent with small flowers is homozygous dominant, and the parent with large flowers is homozygous recessive.

Answer 1

The parents are most likely both heterozygous, having genotypes that produce a 3:1 ratio of dominant to recessive phenotypes in their offspring, which aligns with Mendelian inheritance patterns.

Step-by-step explanation:

The most likely genotypes of the parents in the given genetic cross would depend on the observed traits of the offspring. If we are seeing a mix of traits in the offspring that suggests a 3:1 ratio of dominant to recessive phenotypes, then the parents are most likely both heterozygous for the trait. In genetics, using Mendelian inheritance, homozygous individuals possess two identical alleles (either dominant or recessive), while heterozygous individuals have one dominant and one recessive allele.

Given the context that the offspring of a cross produced 100 homozygous dominant, 100 heterozygous, and 600 homozygous recessive phenotypes, this would be indicative of a cross between two heterozygous parents (Bb x Bb), as this breeding would yield offspring in a 1:2:1 genotypic ratio and a 3:1 phenotypic ratio, consistent with Mendelian inheritance patterns for a single-gene trait.