Which of the following best describes positive gravitropism exhibited by plant roots?
A) It is mediated by auxin similar to the phototropism responses in shoots.
B) It depends on an inhibition of elongation of some cells.
C) Gravity causes gibberellins to accumulate on the lower side of roots.
D) The phenomenon depends upon inhibition of cell elongation of certain root cells by abscisic acid.
E) All of the above are correct.

Question

Quizplus · Accepted Answer

Positive gravitropism in plant roots is mediated by auxin, similar to the phototropism responses in shoots. The auxin moves from the upper side of the root to the lower side due to gravity, causing differential cell elongation and resulting in growth towards the center of the Earth. Gibberellins and abscisic acid do not play a direct role in this phenomenon.

Which of the Following Best Describes Positive Gravitropism Exhibited by Plant