Question

a plant that has round and yellow seeds (rryy) is crossed with a plant that has round and yellow seeds (rryy). what is the ratio of the offspring that will have round and yellow seeds?
key: r = round
r = wrinkled
y = yellow
y = green
1:16
3:16
8:16
9:16

Explanation:

Step1: Analyze the cross for each trait

For the shape trait (R = round, r = wrinkled), we have a cross of Rr × Rr. Using the Punnett square, the genotypic ratio for round (RR or Rr) is 3/4 (since RR:Rr:rr = 1:2:1, so round is 3 out of 4). For the color trait (Y = yellow, y = green), we have a cross of Yy × Yy. The genotypic ratio for yellow (YY or Yy) is also 3/4 (YY:Yy:yy = 1:2:1, so yellow is 3 out of 4).

Step2: Calculate the probability for both traits

To find the probability of having both round and yellow seeds, we multiply the probabilities of each trait. So, (3/4) × (3/4) = 9/16. This means the ratio of offspring with round and yellow seeds is 9:16.

Answer:

9:16