Question

A farmer crossed a yellow maize plant (Yy) with another yellow maize plant (YY). He planted 200 seeds from this cross. How many of the plants would be yellow?

Answer 1

Answer: 200 seeds will be yellow.

Explanation: In this crossing, one parent will produce half of its gametes carrying allele Y and the other half carrying allele y. The other parent will have gametes with allele Y. After fecundation, the offspring could phenotype YY or phenotype Yy.

In genetics, Y is related to the dominant allele and y to the recessive one. In this case, having the Y dominant allele determine the color yellow. Therefore, as all of the offspring has the dominant allele Y for yellow, all of the seeds will be yellow, i.e., 200 seeds will be yellow.