a purple pea plant is crossed with a white flower pea plant. All the f1 plant produced f1 flowers. When the f1 plant is self fertilized. 401 purple flowers and

Question

a purple pea plant is crossed with a white flower pea plant. All the f1 plant produced f1 flowers. When the f1 plant is self fertilized. 401 purple flowers and 131 have white flower. What are the genotypes of the parental f1 and f2

Answer 1

I can't draw the cross for you, but, if there are 401 P flowers and 131 w flowers that result from a cross, then , because P is dominant, the parents (that's the cross of the F1 plants) must be heterozygous :Pw.

 

This is because Pw cross Pw yield 2 Pw, one ww, and one PP.  So, 75% are purple and 25% are white.  

 

Look at the numbers: 131 + 401 = 532

 

131/532 = .25    and 401/532  = .75

 

OK.  The parents of the F1 are PP and Pw because when you cross these, you get 100% Pw.

 

Draw the crosses using the chart in your book.