Question

After a plant is set on a windowsill for several days, its owner comes back to find its stem bent at a sharp angle toward the glass of the window. Which of the following describes this movement of the plant in response to stimuli?

A. Gravitropism
B. Negative phototropism
C. Positive phototropism
D. Thigmotropism

Answer 1

C. Positive phototropism

Step-by-step explanation:

This is a response of plants towards external stimuli. The plant is bent toward the glass of the window because light is coming from the window. It is considered as positive phototropism because it is moving towards the light. The opposite occurs with negative phototropism. In negative phototropism, the movement of plant would be away from the external stimulus.

When you talk about gravitropism, this is the direction of the growth of plants that is affected by gravity. Thigmotropism is the growth response of the plant towards physical touch.