A planet is inhabited by creatures that reproduce with the same hereditary patterns seen in humans. Three phenotypic characters are height (T=tall, t=dwart), head appendages (A=antennae, a=no antennae), and nose morphology (S=upturned snout, s=downturned snout). Since the creatures are not 'intelligent,' Earth scientists are able to do some controlled breeding experiments using various heterozygotes in testcrosses. For tall heterozygotes with antennae, the offspring are tall antennae, 46; dwarf antennae, 7; dwarf no antennae, 42; tall no antennae, 5. For heterozygotes with antennae and an upturned snout, the offspring are antennae upturned snout, 47; antennae downturned snout, 2; no antennae downturned snout, 48; no antennae upturned snout, 3. Calculate the recombination frequencies for both experiments.

Video transcript

Hi everyone here, we have a question that says in a hypothetical organism, coat color wings and high are inherited in the same way that they are in humans. Two alleles for coat color of the organism, our capital E. Equals brown. Lower case B equals white. For its wings are capital W. Equals normal wings. Lower case W. Equals vestigial, and for its height or capital T. Equals tall. Lowercase T. Equals dwarf. A researcher carried out two types of breeding experiments, be in the laboratory and obtained the following results, B. E. One. The breeding between a male with brown coat and normal wings. Hetero zygote and a female with white coat and vestigial wings yielded the following progeny. Brown with normal wings 92 white with normal wings. 14. White with vestigial wings 84. Brown with vestigial wings tin and B. E. To the breeding between a tall male with normal wings, hedgerows, ego and adore female with vestigial wings yielded the following progeny tall. With normal wings 94 dwarf with normal wings. For dwarf, with vestigial wings 96 tall, with vestigial wings six. And the question is, what is the recombination frequencies for breeding experiment one and breeding experiment to. So we're going to use the formula recombination frequency equals recombination offspring divided by total offspring times 100. For breeding experiment one, Our recombination offspring equals our offsprings with brown body and vestigial wings plus our offsprings with white body and normal wings. So that would be 10 plus equals 24. And our total offspring equals 92 plus plus 84 plus 10, Which equals 200. So our recombination frequency equals 24 Divided by times 100 Which equals 12%. Now we're going to do the same thing with breeding experiment too. So our recombinant offspring is going to be dwarfs with normal wings, plus tall, with vestigial wings, so that's going to equal four plus six, which equals 10. And our total offspring Is going to equal plus four plus 96 plus six equals 200. So our recombination recombination frequency equals 10 over times 100 equals 5%. So our answer here is b breeding experiment one equals 12% and breeding experiment two equals 5%. Thank you for watching. Bye.