The F2 generation from a dihybrid cross produced a total of 219 tall plants with
ID: 188836 • Letter: T
Question
The F2 generation from a dihybrid cross produced a total of 219 tall plants with purple flowers, 72 dwarf plants with purple flowers, 69 tall plants with pink flowers, and 31 dwarf plants with pink flowers.
1: please state your hypothesis and explain how you arrived at this prediction
2:
3: What is the chi-square value between the observed and expected offspring from the F2 generation for this dihybrid cross? (2 mark) Please report your chi-square value with 3 decimal places .
(a) What is the degrees of freedom for this dihybrid cross? Blank 1 (1 mark)
(b) What is the probability associated with your calculated chi-square value for this dihybrid cross? (2 marks)
Blank 2 < P < Blank 3
HINT: Make sure you enter the numbers on the correct side of the less than (>) symbols.
phenotype observe expected Purple, tall Purple, dwarf Pink, tall Pink, dwarf total number of plants in F2 generationExplanation / Answer
1. Null hypothesis: The observed values are not deviating from the expected ratio i.e. 9:3:3:1.
2. Test staic:
Category
purple tall
purple dwart
pink tall
pink dwarf
Total
Observed values
219
72
69
31
391
Exptected Ratio
9
3
3
1
16
Exprected Values
219.9375
73.3125
73.3125
24.4375
Deviation
-0.9375
-1.3125
-4.3125
6.5625
D^2
0.878906
1.722656
18.59766
43.06641
D^2/E
0.003996
0.023497
0.253676
1.762308
2.043478
X^2
2.043478
Degrees of freedom
4
-
1
3
3: The chi-square value between the observed and expected offspring from the F2 generation = 2.043
(a) What is the degrees of freedom for this dihybrid cross? = 4-1 = 3
(b) What is the probability associated with your calculated chi-square value for this dihybrid cross? 7.82 at 3 DF and 0.05 probability.
Category
purple tall
purple dwart
pink tall
pink dwarf
Total
Observed values
219
72
69
31
391
Exptected Ratio
9
3
3
1
16
Exprected Values
219.9375
73.3125
73.3125
24.4375
Deviation
-0.9375
-1.3125
-4.3125
6.5625
D^2
0.878906
1.722656
18.59766
43.06641
D^2/E
0.003996
0.023497
0.253676
1.762308
2.043478
X^2
2.043478
Degrees of freedom
4
-
1
3
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.