Two autosomal loci control horn color in unicorns. Pure-breeding gold-horned uni
ID: 272108 • Letter: T
Question
Two autosomal loci control horn color in unicorns. Pure-breeding gold-horned unicorns were mated to pure-breeding silver unicorns. The F1 were all bronze. The F2 generation consisted of 5 gold, 17 bronze, and 7 silver unicorns. Use these data to hypothesize the type of epistasis that is operating here.
Ho: The mode of inheritance for horn color in unicorns is ___________ (answer choices: Single Recessive Epistasis, Single Dominant Epistasis, Duplicate Recessive Epistasis, Duplicate Dominant Epistasis, Duplicate Genes with Cumulative Effect, Dominant/Recessive Epistasis)
A larger experiment was conducted to test the null hypothesis. The F2 generation in the larger data set consisted of 214 bronze-horned unicorns, 68 gold horned unicorns and 88 silver horned unicorns. Conduct the Chi-square test using the larger data set. Round all expected numbers correctly to three decimal digits.
The expected number of Gold Unicorns is ________
The expected number of Silver Unicorns is ________
The expected number of Bronze Unicorns is ________
Rounded to three decimal digits, the calculated chi-square value is ________
The number of degrees of freedom for this test is ________
Rounded to two decimal digits, the critical value is ________
The statistical conclusion is ________ (reject or fail to reject the hypothesis)
PLEASE ANSWER ALL BLANKS TO THIS QUESTION! IT IS ONE QUESTION WITH MULTIPLE BLANKS!
Explanation / Answer
Answer:
1) The mode of inheritance for horn color in unicorns is _Single Recessive Epistasis__________
Explanation: Recessive epistasis: Epistasis due to recessive genotype present at an epistatic locus is called as Recessive epistasis. Or When a character governs by two gene pairs G/g and S/s, recessive gene present at 'g' locus under homozygous condition prevent the expression of genes present at a hypostatic locus.
Horn color is govern by Two genes G/g and S/s. Pure-breeding gold-horned unicorns were mated to pure-breeding silver unicorns. GGSS: Gold, ggss: Silver and GgSs: Bronze
Cross: GGSS X ggss
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F1: GgSs (Bronze) X GgSs
?
9 G_S_ Bronze
3 G_ss Gold
3 ggSS silver
1ggss Silver
The ratio Is 9:3:4.
2) In larger experiment:
214 bronze-horned unicorns, 68 gold horned unicorns and 88 silver horned unicorns. So expected ratio is 9:3:4.
Total number of individuals: 370
The expected number of Gold Unicorns is __69.375
The expected number of Silver Unicorns is __92.5__
The expected number of Bronze Unicorns is __208.125
Rounded to three decimal digits, the calculated chi-square value is ___0.410
The number of degrees of freedom for this test is ____2__(n-1: 3-1)
Rounded to two decimal digits, the critical value is ___5.99(5% error)
The statistical conclusion is ________Hypothesis accepted or Fail to rejected.
Total X2 Value< X2 critical value.
0.410< 5.99. So the error values are statistically not significant at error 5%. So given null hypothesis is accepted.
Phenotype Observed (o) Expected (e) o-e (o-e)2 (o-e)2/e X2 Value Bronze 214 208.125 5.875 34.5 0.165 0.165 Gold 68 69.375 -1.375 1.89 0.027 0.027 Silver 88 92.5 -4.5 20.25 0.218 0.218 Total X2 Value 0.410