Question

if a homozygous blue-flowered plant was crossed with a homozygous white-flowered plant, in what proportions would we expect to observe plants resulting from this cross? assume the white-flowered trait is completely dominant.

Answer 1

When crossing a homozygous blue-flowered plant with a homozygous white-flowered plant, with white being completely dominant, all offspring will exhibit the white-flowered phenotype, resulting in a 100% white to 0% blue ratio.

Step-by-step explanation:

If a homozygous blue-flowered plant was crossed with a homozygous white-flowered plant, and we assume that the white-flowered trait is completely dominant, all of the offspring (F1 generation) would display the white-flowered phenotype. This assumes a Mendelian inheritance pattern where white is the dominant color and blue is recessive.

Here is how it works: the blue-flowered plant would have a genotype of bb (homozygous recessive), and the white-flowered plant would have a genotype of BB or Bb if heterozygous white is also visibly white. Since the question specifies that the white trait is completely dominant to blue, this would mean the white plant's genotype is BB (homozygous dominant).

When these plants are crossed, the genetics dictate that all offspring will receive a B allele from the white parent and a b allele from the blue parent, resulting in a genotype of Bb for each offspring. Each offspring, therefore, will display the white flower color. Hence, the proportion of white to blue flowers in the offspring will be 100% white and 0% blue, or in simple fractions, 1:0.