Question

practice with probability
in pea plants, the gene for yellow seed color (y) is dominant over the gene for green seed color (y), and the gene for round seed shape (r) is dominant over the gene for wrinkled seed shape (r).
a heterozygous yellow - seeded, round pea plant (yyrr) is crossed with a homozygous recessive green - seeded, wrinkled pea plant (yyrr).
use the results of the punnett squares below to answer the question.
what is the phenotypic frequency of green, wrinkled pea offspring (yyrr)?
1/4
0
5/16

Explanation:

Step1: Analyze seed color probability

The cross for seed color is \(Yy\times yy\). Using the Punnett square, the probability of \(yy\) (green) is \(\frac{1}{2}\).

Step2: Analyze seed shape probability

The cross for seed shape is \(Rr\times rr\). Using a Punnett - square (similar to the color cross, with \(Rr\) parent giving \(R\) and \(r\) gametes and \(rr\) parent giving \(r\) gametes), the probability of \(rr\) (wrinkled) is \(\frac{1}{2}\).

Step3: Use the multiplication rule for independent events

Since seed color and seed shape are independent traits (Mendel's law of independent assortment), the probability of \(yyrr\) is the product of the probability of \(yy\) and \(rr\). So \(P(yyrr)=\frac{1}{2}\times\frac{1}{2}=\frac{1}{4}\)

Answer:

\(\frac{1}{4}\)