Purebred lines of fruit flies with wild type (tan) body color and stubby bristles are mated...

Purebred lines of fruit flies with wild type (tan) body color and stubby bristles are mated to flies with ebony bodies and normal bristles. The resulting F1 offspring all have a normal wild-type body color and stubby bristles. The F1 flies are crossed with flies recessive for both traits (i.e. ebony bodies and normal bristles).

a. What phenotypes and ratios of phenotypes would you expect to find among the offspring produced by crossing the F1 with flies recessive for both traits?

- I understand this is a 1:1:1:1 ratio --> mostly I need help with b and c below.

b. Assume you found the following results among the offspring.

Wild type body, Stubby bristles 424

Ebony body, Stubby bristles 58

Wild type body, Normal bristles 62

Ebony body, Normal bristles 456

How could you explain these results?

c. Support your hypothesis in question 6b by performing Chi Square analysis:

Calculate the Chi Square value. (Show your work.)

How many degrees of freedom?

What is the p value? State your conclusion based on your p value.

Expert Solution

genius_generous answered 2 years ago

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