Question

Lab Exercises Part II: Cats In domestic cats there are many genes that affect coat colour and pattern. One of these loci is called spotting. Phenotypes associated with alleles at the spotting locus are incompletely dominant. Homozygous individuals of one type (SS) have white hair on more than 50% of their bodies, heterozygous individuals (Ss) have white hair on less than 50% of their bodies (commonly confined to underparts such as the legs/feet, belly, and chin), and homozygous individuals of the other type (ss) have no white hair at all. (See the online content of this lab for a photo illustrating the differences between SS, Ss, and ss cats.) You are interested in investigating microevolution at the spotting locus of domestic cats in your city. To collect data from a representative sample, you study photographs of cats that are up for adoption at local cat shelters. 5. In the 100 photos that you examine, 41 cats have white hair on more than 50% of their bodies, 24 cats have white hair on less than 50% of their bodies, and 35 have no white hair at all. Add this information to the appropriate cells in the 'Observed #" column in Table 4. 6. Use the data to determine the S and s allele frequencies at the spotting locus. Show your work and/or reasoning. RESPONSE:

Answer 1

5. Kindly note down in the activity coloumn.

6.Frequency of allele S = frequency of genotype SS + 1/2 frequency of genotype Ss

Frequency of allele S = 41/100+24÷200=0.53

Frequency of allele s = frequency of genotype ss + 1/2 frequency of genotype Ss

Frequency of allele s= 35/100 + 24÷200= 0.47