Question

In the summer squash, fruits may be white, yellow, or green. In one case, the cross of yellow X white produced an F1 of all white-fruited plants that, when selfed, gave an F2 segregating 12 white: 3 yellow: 1 green. (a) suggest gnotypes for the white, yellow, and green phenotypes. (b) give genotypes of the P, F1, and F2 of this cross.
Biology genetics - bobpursley Friday, January 5, 2018 at 11:04pm
P: Yg x WW yellow x white
F1: YW,YW, gW, gW all white
F2:
first two YY,YW,WW,YW one Yel, 3W
first, third Yg,YW,Wg,WW one Yel, 3W
first, fourth Yg,YW,Wg,WW one Yel, 3W
second third Yg,YW,Wg,WW one Yel, 3 W
third, fourth gg,gW, Wg, WW one g, 3W
now if W dominates to y,g, and Y dominates to g, then I count 15/20 W, 1/20 g, and 3/20 yellow
Now in the F2 above, there were 12/16 W,3/16 Yellow, and 1/16 green Those frequencies look very close to what I laid out.
White 12
Yellow 4
green


I have tried many ways and cannot figure out the answers provided. Could you please show me how you came up with these answers?

Answer 1

Jiskha doesn't have a biology expert at present, but you might be able to find information here:
https://www.khanacademy.org/science/biology

Scroll down to the sections that include "genetics" in their titles and you might find the information you need.