Question

Heterozygous female fruit flies with gray body and purple eyes were mated with homozygous males with black body and red eyes. The number of offspring obtained and their phenotypes are shown below: 

Calculate the recombination frequency. 
 

Hint:

Recombination frequency is calculated by dividing the number of recombinant offspring by the total number of offspring.

Answer 1

Correct Answer: 15

Step 1: Understanding recombination frequency.
Recombination frequency is the percentage of offspring that inherit a recombinant genotype. Recombinant offspring are those that show a new combination of traits. In this case, the gray body–red eyes (61 offspring) and black body–purple eyes (55 offspring) are recombinant.
Step 2: Calculating recombination frequency.
Total number of offspring = 300 + 347 + 61 + 55 = 763
Total recombinant offspring = 61 + 55 = 116
Recombination frequency = \( \frac{116}{763} \times 100 = 15.2% \)
Step 3: Conclusion.
The recombination frequency is approximately 0.13 or 13%.