AP BIOLOGY

Detailed explanation-1: -Thigmotropism describes plant growth in response to touch or contact with a solid object. Positive thigmostropism is demonstrated by climbing plants or vines, which have specialized structures called tendrils. A tendril is a thread-like appendage used for twinning around solid structures.

Detailed explanation-2: -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. An example of negative thigmotropism is the growth of roots underneath the soil.

Detailed explanation-3: -Complete Answer:-Stems of the plant show negative geotropism while the roots show positive geotropism.

Detailed explanation-4: -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.