The field of genetics has demonstrated that both molecular and transmission genetics characterize the same hereditary processes at different levels. For example, the wrinkled seed phenotype used by Mendel results from a defect in the gene that encodes which of the following products?

(A) gibberellin 3-[beta] hydroxylase, an enzyme required for synthesis of the growth factor gibberellin

(B) an enzyme that catalyzes a step in the breakdown of chlorophyll

(C) a transcription factor that activates the expression of genes required for anthocyanin production

(D) starch-branching enzyme

The wrinkled seed phenotype used by Mendel results from starch branching enzyme.

Explanation:

During mono hybrid cross, Mendel took 2 types of pea plant of which one was tall (TT) and another pea plant was (tt). After crossing, he observed that in F1 generation the ratio of tall and dwarf plant was 3:1

He observed that there is a particular enzyme which causes formation of dwarf plant as the enzyme is absent in wrinkle offspring but present in the round offspring, The enzyme is called as starch branching enzyme.

Thus failure in the formation of this enzyme produce complex metabolic consequences on starch, protein and lipid biosynthesis.