The arrangement of xylem in stem is

Options

A. Endarch
B. Mesarch
C. Exarch
D. Both 1 and 2

Answer

**Step-by-Step Solution:**

1. **Understanding Xylem**: Xylem is a type of vascular tissue in plants responsible for the transport of water and minerals from the roots to the rest of the plant. It also provides structural support.

2. **Types of Xylem Arrangements**: There are different arrangements of xylem in plant stems, primarily categorized as endarch, exarch, and mesarch.

3. **Endarch Arrangement**: In the endarch arrangement, the protoxylem (the first-formed xylem) is located towards the periphery of the stem, while the metaxylem (the later-formed xylem) is positioned towards the center. This arrangement is typical in the stems of flowering plants.

4. **Exarch Arrangement**: In contrast, the exarch arrangement has the protoxylem directed towards the periphery and the metaxylem towards the center, but this arrangement is commonly found in the roots of most plants.

5. **Mesarch Arrangement**: The mesarch arrangement features the protoxylem developing first in the center and then extending both centrifugally (outwards) and centripetally (inwards). This arrangement is often observed in the shoots of ferns.

6. **Conclusion**: Based on the definitions and examples provided, the arrangement of xylem in the stem of flowering plants is classified as endarch.

**Final Answer**: The arrangement of xylem in the stem is endarch.

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