Which statements describe thigmotropism? Check all that apply.

Thigmotropism is a plant’s response to touch.
Thigmotropism is a plant’s response to an external stimulus.
Thigmotropism occurs only slowly.
Thigmotropism can occur quickly or slowly.
Thigmotropism may involve the way in which a plant grows.
Thigmotropism may involve the closing and opening of plant leaves.