Question

We did a lab about the maternal inheritence in Brassica Rapa- it is uniparental and maternal. so,

Cross 1: Varigeated Female x Wild type male: progeny had white, green, and variegated

Cross 2: Variegated Male x wild type feamle: progeny all green

There is a question that confuses me that i cant answer:

1.)    How would your observations of the F1 generation have differed if the variegation was controlled by a recessive nuclear gene?

b. By a dominant nuclear gene?

Answer 1

It is given that leaf color in Brassica is uniparental and maternal.

Cross 1: Variegated Female x Wild-type male: progeny had white, green, and variegated

Cross 2: Variegated Male x wild-type female: progeny all green

If the leaf color is regulated by a recessive nuclear gene,

Assumptions:

1. All the parents are pure lines

2. variegated phenotype is due to a recessive nuclear mutation.

Cross 1: Variegated Female x Wild-type male: All progeny shows WT phenotype

Cross 2: Variegated Male x wild-type female: All progeny shows WT phenotype

If the leaf color is regulated by a dominant nuclear gene,

Assumptions:

1. All the parents are pure lines

2. variegated phenotype is due to a dominant nuclear mutation.

Cross 1: Variegated Female x Wild-type male: All progeny shows the variegated phenotype

Cross 2: Variegated Male x wild-type female: All progeny shows the variegated phenotype