Ectophloic siphonostele is found in

Options

A. Osmunda and Equisetum
B. Adiantum and Cucurbitacease
C. Marsilea and Botrychium
D. Dicksonia and Maiden hair fern

Answer

To determine where ectophloic siphonostele is found, we can follow these steps:

### Step 1: Understand the term "ectophloic siphonostele"
- Ectophloic siphonostele is a type of vascular arrangement in plants. In this arrangement, the phloem is located outside the xylem.

### Step 2: Identify the characteristics of siphonostele
- A siphonostele consists of a central core of pith surrounded by xylem and phloem. In the ectophloic type, the phloem is located outside the xylem.

### Step 3: Review the options provided
- The options given are:
1. Osmunda and Equisetum
2. Adiantum and Pteris
3. Marsilea and Portulaca
4. Tixonia and Maidenhair fern

### Step 4: Analyze the options
- We need to identify which of these plant groups is known to have ectophloic siphonostele.

### Step 5: Recall examples of ectophloic siphonostele
- Ectophloic siphonostele is typically found in certain ferns. Osmunda is a genus of ferns that is known to exhibit this type of vascular arrangement.

### Step 6: Select the correct option
- Based on the information, Osmunda and Equisetum are known to have ectophloic siphonostele.

### Final Answer
- Ectophloic siphonostele is found in **Osmunda and Equisetum**.

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