As new modes of transportation and commerce have developed, the movement of humans around the Earth has increased dramatically over time.
What evolutionary process has increased as a result?
A. Stabilizing selection
B. Directional selection
C. Genetic drift
D. Gene flow

one is through turgidity. this occurs before ground tissue ( collenchyma

and sclerenchyma cells) become well

developed to give structural support to the plant as it grows bigger. the xylem

tissue (composed of rigid tissue) of the young

plant render this support and also maintaining osmotic turgidity of the surrounding

plant cells.