Question

Name the organ/part of a plant which shows:

1. Positive hydrotropism
2. Positive phototropism
3. Negative geotropism
4. Positive chemotropism

Answer 1

1. Positive Hydrotropism:
The organ exhibiting positive hydrotropism is the roots. Roots direct their growth towards water sources, responding to soil moisture gradients.

2. Positive Phototropism:
The organ exhibiting positive phototropism is the stem. Stems orient towards light to optimize sunlight absorption for photosynthesis.

3. Negative Geotropism:
The organ exhibiting negative geotropism is the stem. Stems grow upward, counteracting Earth's gravitational force.

4. Positive Chemotropism:
The organ exhibiting positive chemotropism is the pollen tube. The pollen tube elongates towards the ovule, guided by chemical signals for fertilization.