Peripheral protoxylem and central metaxylem is

Options

A. Endarch and found in stems
B. Exarch and found in stems
C. Endarch and found in roots
D. Exarch and found in roots

Answer

To answer the question regarding the relationship between peripheral protoxylem and central metaxylem, we can break it down step by step:

### Step 1: Understand the Types of Xylem
- **Primary Xylem** is divided into two types: **Protoxylem** and **Metaxylem**.
- **Protoxylem** is the first xylem to develop and is typically smaller in diameter.
- **Metaxylem** develops later and is larger in diameter.

**Hint:** Remember that protoxylem is the first to form, while metaxylem forms later.

### Step 2: Identify the Arrangement of Xylem
- The arrangement of protoxylem and metaxylem can vary depending on the plant organ (stem or root).
- In stems, when protoxylem is located at the center and metaxylem is on the periphery, this is known as the **engulf condition**.
- Conversely, when protoxylem is on the periphery and metaxylem is central, this is known as the **x-arc condition**.

**Hint:** Focus on the position of protoxylem and metaxylem to differentiate between engulf and x-arc conditions.

### Step 3: Determine Where Each Condition is Found
- The **engulf condition** (protoxylem in the center, metaxylem peripheral) is typically found in the **stem**.
- The **x-arc condition** (protoxylem peripheral, metaxylem central) is found in the **roots**.

**Hint:** Associate the engulf condition with stems and the x-arc condition with roots.

### Step 4: Conclusion
- The question asks about the relationship between peripheral protoxylem and central metaxylem.
- Based on the definitions, peripheral protoxylem and central metaxylem indicate the **x-arc condition**, which is characteristic of roots.

**Final Answer:** Peripheral protoxylem and central metaxylem refer to the x-arc condition, which is found in the roots.