The tips of some rice seedlings were cut off while some were left intact. Both were covered with a container which had not only one small hole to allow light through. After twenty-four hours it was observed that
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Correct Answer: Option B
Explanation:
The correct answer is B: the cut tips bent towards the source of light.
Explanation:
The tips of rice seedlings, like other plants, exhibit phototropism, which is the plant's growth response to light. In this experiment:
- The intact tips (which are the growing parts of the plant) are capable of detecting and responding to light, and they will bend towards the light source (positive phototropism).
- When the tips are cut off, the plant can no longer directly sense the light with the tip, but the rest of the plant may still grow towards the light, as the signal to bend towards the light (caused by the hormone auxin) can still travel from the base of the plant to the rest of the stem.
This demonstrates that light sensing and bending (phototropism) occurs in the tip of the seedling, and removing the tip would result in a less direct response, but still, the plant bends towards the light source, particularly due to the remaining response mechanisms in the lower parts of the plant.
The correct answer is B: the cut tips bent towards the source of light.
Explanation:
The tips of rice seedlings, like other plants, exhibit phototropism, which is the plant's growth response to light. In this experiment:
- The intact tips (which are the growing parts of the plant) are capable of detecting and responding to light, and they will bend towards the light source (positive phototropism).
- When the tips are cut off, the plant can no longer directly sense the light with the tip, but the rest of the plant may still grow towards the light, as the signal to bend towards the light (caused by the hormone auxin) can still travel from the base of the plant to the rest of the stem.
This demonstrates that light sensing and bending (phototropism) occurs in the tip of the seedling, and removing the tip would result in a less direct response, but still, the plant bends towards the light source, particularly due to the remaining response mechanisms in the lower parts of the plant.