Question

What is feedback tropism?

Answer 1

Tropism

When you hear a loud noise, you may respond by jumping. External stimuli result in a response. We easily see this in animals, but it also happens in plants. We generally think of plants as passive. They simply - and much of the time, very slowly - grow. However, there is much more to plants than we perceive.

The way sunflowers turn in the direction of the sun throughout the day is an example of phototropism

When animals, including humans, respond to a stimulus (which is something that causes a response), we call it a reaction. For example, if someone touches your arm, you generally turn to react. In plants, the response to a stimulus is known as a tropism. This plant movement toward or away from a stimulus can come in many forms. Before we look at a few, let's better understand the word tropism. Like many words in science, tropism comes from a Greek word. Tropos means 'to turn'. Therefore, a tropism is a turn towards or away from a stimulus. When the movement is towards the stimulus, it is called positive tropism. Likewise, when the movement is away from the stimulus, it is called negative tropism. While there are several forms of tropism, we'll just focus on three key types: phototropism, geotropism and thigmatropism.