Get expert advice and insights on any topic with IDNLearn.com. Get accurate answers to your questions from our community of experts who are always ready to provide timely and relevant solutions.

In pea plants, the allele for yellow seeds [tex]$(Y)$[/tex] is dominant and the allele for green seeds [tex]$(y)$[/tex] is recessive. Two plants with the following genotypes are crossed:
[tex]$
Yy \times Yy
$[/tex]

What ratio of yellow seeds to green seeds should you expect in the offspring?

A. 3:1
B. [tex]$4:0$[/tex]
C. 2:2
D. [tex]$1:3$[/tex]


Sagot :

Let's analyze the cross between two pea plants and determine the expected ratio of yellow seeds to green seeds in the offspring.

The genotypes of the parent plants are [tex]\( YY \)[/tex] and [tex]\( Yy \)[/tex]. Here, [tex]\( Y \)[/tex] represents the dominant yellow allele and [tex]\( y \)[/tex] represents the recessive green allele.

When we cross these two plants, we can use a Punnett square to visualize the genotypic combinations of the offspring.

The Punnett square for this cross is as follows:

[tex]\[ \begin{array}{c|c|c} & Y & Y \\ \hline Y & YY & YY \\ \hline y & Yy & Yy \\ \end{array} \][/tex]

From the Punnett square, we obtain the following genotypes for the offspring:
- [tex]\( YY \)[/tex]
- [tex]\( YY \)[/tex]
- [tex]\( Yy \)[/tex]
- [tex]\( Yy \)[/tex]

Now, let's count the number of each genotype:
- Two offspring have the genotype [tex]\( YY \)[/tex].
- Two offspring have the genotype [tex]\( Yy \)[/tex].

Both [tex]\( YY \)[/tex] and [tex]\( Yy \)[/tex] result in yellow seeds because the yellow allele [tex]\( Y \)[/tex] is dominant.

Therefore, all four offspring will have yellow seeds.

As a result, the ratio of yellow seeds to green seeds in the offspring is [tex]\( 4:0 \)[/tex].

Thus, the correct answer is:

B. [tex]\( 4 : 0 \)[/tex]