<span>It may be subjected to the number of dissimilar genes in the punnet square. In the characteristic Aa v Aa square it is a 1:2:1 ratio, 25% AA, 50% Aa, and 25% aa. These percentages are autonomous of how many offspring, for instance if you have 3 in a row that are AA the probabilities that the next one will be AA are identical as in the original.</span>

5 0

3 years ago

In Drosophila, the bar mutant is characterized by eyes that are restricted to a narrow, vertical bar. When a bar female is mated

Lelechka [254]

Answer:

See the answer below

Explanation:

a) The mode of inheritance of the bar mutant is X-linked and dominant.

Assuming that barness is represented by the allele B.

Bar female = $X^BX^B$ or $X^BX^b$

Wild type male = $X^bY$

Bar female x wild type male:

$X^BX^B$ x $X^bY$

$X^BX^b$ $X^BY$ $X^BX^b$ $X^BY$

All of the F1 flies are bar because a single B allele is required for the trait to be expressed.

Bar male x wildtype female

$X^BY$ x $X^bX^b$

$X^BX^b$ $X^BX^b$ $X^bY$ $X^bY$

All the female offspring are barred while all the males are wildtype barred resulting in a 50/50 (857/905 is approximately 50/50) ratio of barred/wildtype offspring.

b) Genotypes of each of the cross above, including the parents and the F1 generations.

1. $X^BX^B$ x $X^bY$

$X^BX^b$ $X^BY$ $X^BX^b$ $X^BY$

2. $X^BY$ x $X^bX^b$

$X^BX^b$ $X^BX^b$ $X^bY$ $X^bY$

4 0

3 years ago