AP BIOLOGY

Detailed explanation-1: -Thigmotropism is when plants grow in response to touch or contact with objects. For example, vines have small tendrils that curl around walls or trellises. Plants like this don’t usually have strong stems. So, thigmotropism helps them stay upright and keep growing.

Detailed explanation-2: -Thigmotropism can be used in ways that increase the chance of a plant catching light for photosynthesis. Thigmotropism is one example of tropism, which is the responding of a plant to environmental stimuli by growing towards or away from them. In other words, the reaction can be positive or negative.

Detailed explanation-3: -It allows the plant to climb up and gain more sunlight for photosynthesis, rather than stay on the forest floor / down and get less light. It allows for more seed dispersal so that the plants can increase their numbers.

Detailed explanation-4: -A positive thigmotropism is a response towards the touch stimulus whereas a negative thigmotropism is a response away from the touch stimulus. Examples of positive thigmotropism are the growth of ivy on walls upon contact to walls and the coiling of tendrils or twiners upon contact to objects for support.