We Know from the Experiments of the Past That Plants

Question

We know from the experiments of the past that plants bend toward light because
A) they need sunlight energy for photosynthesis.
B) the sun stimulates stem growth.
C) cell expansion is greater on the dark side of the stem.
D) auxin is inactive on the dark side of the stem.
E) phytochrome stimulates florigen production.

Accepted Answer

Cell expansion is greater on the dark side of the stem, which causes the plant to bend toward the light. This phenomenon is part of phototropism, where plants grow towards a light source. The differential growth is due to uneven distribution of plant hormones like auxin, which promotes cell elongation more on the shaded side.