What rapid botanical response causes the leaflets of the sensitive plant (Mimosa pudica) to collapse and fold inwards within seconds of being touched?
Answer and explanation
Correct answer: D. thigmonastic turgor loss in pulvinus motor cells at the base of petiolules
- Step 1: When touched, an electrical action potential travels through the petiole. Step 2. Specialized swollen motor organs (pulvini) at leaf bases rapidly expel potassium and water from lower cells. Step 3. Sudden loss of turgor causes the leaflets to collapse rapidly. This is a non-directional (nastic) response to touch. Answer: thigmonastic turgor loss in pulvinus motor cells at the base of petiolules. Why not the others: It is reversible turgor movement, not growth elongation, phototropism, or cellulose synthesis.
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