Choose the incorrect match from the following with regard to function of modified stems

Options

A. Photosynthetic stem - Opuntia, Euphorbia
B. Reproductive stem - Dioscorea, Agave
C. Protective stem - Grapevines, Asparagus
D. Climbing stem - Watermelon, Cucumber

Answer

To solve the question regarding the incorrect match with respect to the function of modified stems, we will analyze each option provided in the question step by step.

### Step 1: Understand the Concept of Modified Stems
Modified stems are adaptations that serve specific functions beyond the typical role of a stem, which is primarily to support leaves and transport nutrients and water. These modifications can serve various purposes such as photosynthesis, storage, reproduction, and support.

### Step 2: Analyze Each Option
1. **Photosynthetic Stem: Opuntia and Euphorbia**
- **Opuntia** (Cactus): The stem is modified to perform photosynthesis, especially in arid environments where leaves are reduced to spines to minimize water loss.
- **Euphorbia**: Similar to Opuntia, it has a modified stem that carries out photosynthesis.
- **Conclusion**: This match is correct.

2. **Reproductive Stem: Dioscorea and Agave**
- **Dioscorea**: Known for its tuberous roots, it can reproduce vegetatively through its modified stem.
- **Agave**: It produces bulbils (modified axillary buds) that can grow into new plants.
- **Conclusion**: This match is also correct.

3. **Protective Stem: Grapevine and Asparagus**
- **Grapevine**: It is a climbing plant, and its stem helps in climbing rather than providing protection.
- **Asparagus**: The stem is modified for food storage, not primarily for protection.
- **Conclusion**: This match is incorrect as it does not accurately describe the function of the grapevine and asparagus stems.

4. **Climbing Stem: Watermelon and Cucumber**
- **Watermelon**: It has a climbing stem that helps it to grow upwards.
- **Cucumber**: Similarly, it has a stem that supports climbing.
- **Conclusion**: This match is correct.

### Step 3: Identify the Incorrect Match
From the analysis, the incorrect match is the third option regarding the protective stem. The grapevine is primarily a climbing plant, and asparagus is not a protective stem but rather a storage stem.

### Final Answer
The incorrect match is **Protective Stem: Grapevine and Asparagus**.

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