Question

What is the phenotypic ratio of the offspring

Answer 1

9:3:3:1

Step-by-step explanation:

9 of the 16 possible genotypes have a capital R and a capital Y. This means they all have the phenotype of round and yellow.

3 out of 16 have small r's and at least one capital Y. This gives a three in 16 chance for a crippled yellow phenotype. similarly, there's a 3 out of 16 chance to get the phenotype of round green phenotype.

There is only a 1 in 16 chance to get the phenotype of crippled green. Putting these numbers in a ratio gives 9:3:3:1.

Answer 2

To predict the phenotypic ratio of offspring, we can use a Punnett square for monohybrid and dihybrid crosses, resulting in 1:1 or 3:1 ratios respectively for simple crosses, and more complex ratios such as 9:3:3:1 for a dihybrid cross involving two heterozygous parents.

To predict the phenotypic ratio of the offspring from a cross between two pea plants, we can use a Punnett square. For a cross between a dwarf pea plant (homozygous recessive) and a tall pea plant (heterozygous), the phenotypic ratio is calculated considering that the dwarf trait (short plant) is recessive and the tall trait is dominant.

Thus, from the given genotype, every tall pea plant (Tt) when crossed with a dwarf plant (tt) would result in a 1:1 phenotypic ratio of tall (Tt) to dwarf (tt) plants. Similarly, when crossing two heterozygous tall pea plants (Tt x Tt), the expected phenotypic ratio is 3:1 for tall (TT or Tt) to dwarf (tt) offspring.

For a dihybrid cross, which considers two traits simultaneously, such as seed shape and color, the expected ratio is 9:3:3:1 if both parents are heterozygous for both traits. This is reduced to two separate 3:1 ratios for each trait when analyzed independently.