Answer:
a. 1/64 AATTDD
b. 1/64 aattdd
c. 8/64=1/8 AaTtDd
d. 2/64 = 1/32 AATTDd or aattDd or AAttDd or aaTTDd
Explanation:
<u>Available data:</u>
- Flower position: Axial (A) is dominant to Terminal (a)
- Stem length: Tall (T) is dominant to dwarf (t)
- Seed shape: Round (R) is dominant to wrinkled (r)
<u>Cross</u>:
Parental) AaTtDd x AaTtDd
Knowing that these four genes assort independently, then we can infer that the F1 will have the next genotypic proportions for each gene:
Aa =2/4
aa = 1/4
Tt = 2/4
tt = 1/4
Dd = 2/4
dd = 1/4
<em>This is the same as developing a Punnett square for each gene separately.</em>
Knowing this, to get each of the mentioned genotypes for each trait, we must multiply their respective genotypic proportions, like this:
a. homozygous for the three dominant traits, AATTDD
AA1/4 x TT 1/4 x DD 1/4 = AATTDD 1/64
b. homozygous for the three recessive traits, aattdd
aa 1/4 x tt 1/4 x dd 1/4 = aattdd 1/64
c. heterozygous for all three characters, AaTtDd
Aa 2/4 x Tt 2/4 x Dd 2/4 = AaTtDd 8/16=1/8
d. homozygous for axial and tall, heterozygous for seed shape. There are four possibilities, all of them with the same result:
AATTDd --> 1/4 x 1/4 x 2/4 = 2/64=1/32
aattDd ---> 1/4 x 1/4 x 2/4 = 2/64=1/32
AAttDd ---> 1/4 x 1/4 x 2/4 = 2/64=1/32
aaTTDd ---> 1/4 x 1/4 x 2/4 = 2/64=1/32
