In Drosophila, the allele dp+ determines long wings and dp determines short (“dumpy”) wings. At a separate locus e + determines gray body and e determines ebony bodyy. Both loci are autosomal. The original parents were pure-bred with antagonistic traits, one of the parents had long wings and ebony body. The dihybrid F1 was test crossed with the following results:

Phenotype , Number: (Long, ebony 15) (Long, gray 136) (Short, gray 140) (Short, ebony 145)

You want to determine if the data support whether the genes are linked or sort independently by using the Chi Square test.

a. State the null hypothesis for this experiment.

b. Calculate the X2 value. You must show your work below: 

c. Determine the degrees of freedom and give the p-value range.

d. What does the p-value mean ( In other words, what % of the time you would expect the deviation from expected to occur by chance)?

e. What is your conclusion?

f. What was the genotype of the original parents?

g. Show the inferred chromosomal constitutions of the parents, the F1, the F1 tester, and the progeny. You can do by drawing a pair of parallel lines that represents each chromosome. Indicate the allele or alleles that are on each chromosome above or below the line. If you determined that the genes are linked, then both genes will be on the same chromosome. If they assort independently, then two sets of chromosomes must be drawn, one for each gene.