Identify the incorrect statements from the following
1. Young stem of vine plant show positive phototropism and positive thigmotropism
2. Sunflower position itself facing the sun is showing positive response to heat generated due to exposure to sunlight
3. Roots show negative thigmotropism and positive hydrotropism
4. Roots show positive chemotropism to some chemical and negative chemotropism to some other chemicals
2
Sunflower follows the movement of sun. It positions itself facing the sun always even when the sun appears to move across the sky. The response exhibited by the sunflower to sun is an example for heliotropism. Heliotropism is the movement of plants tracking the sun. Vine plant stems grow towards light (positive phototropism) and they coil around any support that comes in their path (positive thigmotropism). Roots on the other hand, grow away from any obstruction that comes in their path (negative thigmotropism) and move towards water (positive hydrotropism). Roots are attracted towards certain chemicals and inhibited by some other chemicals (both positive and negative chemotropism).