Many Valuable Horticultural Varieties of Plants, Including Roses, Rhododendrons, Junipers

Multiple Choice

Many valuable horticultural varieties of plants, including roses, rhododendrons, junipers, geraniums, and so on, are commonly propagated by inducing roots to form on cuttings taken from branch tips. This method involves cutting a few inches from the tip of a branch and inserting the cut end into moist sand or other substrate. Under the right conditions, roots may form from the cut end, giving a new plant generated from the stem cutting. Which of the following hypotheses is the LEAST likely, given the observation of roots forming from a cut stem?

A) genome reduction hypothesis
B) differential gene expression hypothesis
C) differential cell signaling hypothesis
D) epigenetic regulation hypothesis