In mummies, gray (G) is dominant to black (g), Sleek (S) is dominant to pudgy (s

ID: 273490 • Letter: I

Question

In mummies, gray (G) is dominant to black (g), Sleek (S) is dominant to pudgy (s) and friendly (F) is dominant to mean (f). All loci are autosomal.

Po: Pure-breeding black, sleek , mean mummies were mated to pure-breeding gray, pudgy, friendly mummies.

The F1 were testcrossed. (Testcross used: HOMOZYGOUS RECESSIVE for all alleles)

Based on the map below and a coefficient of coincidence of 0.9, determine the frequency of each phenotype in the testcross progeny. Round each answer to 5 decimal digits.

I________________________I_____________________________I

a.)What is the frequency of gray, sleek testcross progeny?

b.)What is the frequency of gray, friendly testcross progeny?

c.)What is the frequency of black, friendly testcross progeny?

d.)What is the frequency of black, pudgy, mean testcross progeny?

e.)What is the frequency of gray, pudgy, friendly testcross progeny?

f.)What is the frequency of gray, sleek, mean testcross progeny?

g.)What is the frequency of pudgy, friendly testcross progeny?

h.)What is the frequency of pudgy, mean testcross progeny?

Color Body Type Disposition 16cM 3cM

Explanation / Answer

We have denoted gray with B and black with b

bSf xBsF

F1 = BbSsFf

Testcross

BbSsFf X bbssff

bsf

BSF

BbSsFf

BsF

BbssFf

BSf

BbSsff

Bsf

BBssff

bSF

bbSsFf

bsF

bbssFf

bSf

bbSsff

bsf

bbssff

a.)What is the frequency of gray, sleek testcross progeny?

Ans. Expected = 2/8 = ¼= 0.25