Question

Chemical X is produced by a plant species with a general type that contains 2 alleles of a certaingene. Chemical Z is produced by another plant or the same species with a general type thatcontains a different pair of alleles for the same gene. when two true breeding plants arecrossed the offspring produced both chemicals X&Z. which mode of inheritance isdemonstrated by these observations?A. CodominanceB. dominanceC. polygenicD. sex linked

Answer 1

In this case, we are talking about two purebred plants, that is, homozygous for a characteristic. This means that the plant producing chemical X will have two X alleles (XX) and the other plant will have two Z alleles (ZZ).

First, we make the punnet's chart to obtain the possible offspring:

Since it is not specified that one of the alleles is dominant over the other and since both phenotypes are expressed in the offspring, it means that we are talking about a case of codominance. Codominance occurs when two alleles that produce different characteristics are expressed but do not mix and also do not have dominance over each other. An example is a red and a white flower, in which if there is codominance we will obtain a red-white speckled flower (both colors are expressed and not mixed)