NEET BIOLOGY

Detailed explanation-1: -In essence the poison ivy is using the fence, tree, or structure it touches for support as it continues its growth. This concept of poison ivy’s directional growth for support in response to touch is known as thigmotropism.

Detailed explanation-2: -Thigmotropism behavior causes the creeping plant to grow and coil around the tree and grow in an upward direction towards it. Ivies often use trees for climbing support. Some house or garden plants also show thigmotropic behavior, such as Morning glory, periwinkle, Money plants, Passion vines, Ivy plant, etc.

Detailed explanation-3: -Positive thigmotropism is when a plant grows toward a contact stimulus. For example, when a climbing plant such as ivy grows along a wall, it is using its sense of touch to continue its growth. Climbing plants will also release a hormone called auxin.

Detailed explanation-4: -Thigmotropism is the type of tropic movement which occurs in response to touch. Similarly, phototropism, chemotropism and hydrotropism occur in response to light, chemicals and water respectively.