Mendelian Genetics and Chi Square - (Sep/28/2009 )

A poultry geneticist made reciprocal crosses between two true-breeding strains of fowl,
one with rose combs and white feathers, and the other with single combs and black
feathers. The F1 phenotypes were not recorded, but the F1 were crossed with the truebreeding
chickens with rose combs and white feathers and the true-breeding chickens
with single combs and black feathers. The results are the crosses are shown.



Make a hypothesis concerning the number of genes involved and the allelic relationship
for each gene. Choose appropriate notation and indicate the genotypes of the parents,
gametes produced by them and the resulting genotypes and phenotypes in each cross,
byusing a Punnett Square or Branch Diagram. Test your hypothesis using the data from
each cross with a Chi Square Test.

Homework - what do you think the answer is! We won't help you unless you help yourself!

Based on the numbers it seems that black & white are codominant, and rose is dominant over single. Also the parent that was crossed with the "rose comb,white" would have the genotype of "RR/rr/Rr BW" and the other parent that was crossed with the "single comb,black" would have the genotype of "RrBW". I just need help with the Chi Square calculations.

Much better: This link should help you: http://www.ndsu.nodak.edu/instruct/mcclean...del/mendel4.htm