According to the acid growth hypothesis, auxin works by
A) dissolving sieve plates, permitting more rapid transport of nutrients.
B) dissolving the cell membranes temporarily, permitting cells that were on the verge of dividing to divide more rapidly.
C) changing the pH within the cell, which would permit the electron transport chain to operate more efficiently.
D) increasing wall plasticity and allowing the affected cell walls to elongate.

Question

Quizplus · Accepted Answer

The acid growth hypothesis proposes that auxin works by increasing wall plasticity in the affected cells, allowing them to elongate. This is achieved through the activation of proton pumps, which pump hydrogen ions out of the cell, lowering the pH in the cell wall. The acidic environment activates enzymes that break down the cell wall, allowing the cell to become more plastic and expand. The result is elongation of the cell and, ultimately, growth of the plant organ.

According to the Acid Growth Hypothesis, Auxin Works by