genetic question?

Question

According to Mendel's first law, allels A and a of a particular gene segregate fromo each other and appear in equal number among the gamates. But Mendel did not know that his plants were diploid. Let us assume that Mendel's plants were teraploid(4N), that evrey gamete contains two alleles, and that the distribution of alleles to gametes is random. Suppose we have a cross of AAAA*aaaa, where A is dominant, regardless of the number of a alleles present in an individual.

The question are:

a)what will b ethe genotype of the F1 peas?

b) If the F1 peas are selfed, what will be the phenotypic ratio in the F2?(Hint: label the four allels to produce the gametes, then predict the frequency of each type of gametes)

please help and explain..thank you..=)

Answer 1

chicky has made your F1 an octaploid! The F1 will be AAaa

b) there are 16 combinations in the selfed F2

aaaa = 1
AAAA =1
AAaa = 6
Aaaa = 4
AAAa = 4

Answer 2

a) F1= AaAaAaAa
Say you get 'A' form the dad, and 'a' form the mom, when the gametes come together for the first generation you get 50% from mom and 50% from dad, i.e. Aa, and because it is teraploid you should have 4 'A' and 4 'a', hence AaAaAaAa

b) I'm too tired to answer this question seeing as I'd actually have to calculate stuff and I can't remember the ratio off the top of my head, time for bed, good luck with your genetics question