Answer: cause some plant cells to grow longer than others.
Step-by-step explanation:
Auxins have a large range of physiological effects, but they are typically known for their involvement in cell elongation and its synergistic interaction with cytokinins in the regulation of the cell division process. These two hormones, when applied exogenously, control the organogenesis of roots and branches in plant tissues. The effect is dependent on the ratio of auxins to cytokinins, a high ratio of auxins induces root formation, while a high ratio of cytokinins induces the formation of branches.
In other words, this substance promotes the elongation of cells, and one of the main natural occurring auxins is AUXIN. 3-Indolylacetic acid (AIA). It is synthesized at low levels in all tissues, but mainly meristematic apical stem, young leaves, fruits and developing seeds.