The casparian strip prevents water and minerals from entering the stele through the

Options

A. Plasmodesmata
B. Apoplast
C. symplast
D. Xylem vessel

Answer

**Step-by-Step Solution:**

1. **Understanding the Casparian Strip**: The Casparian strip is a band of cell wall material that is impregnated with suberin, a waxy substance. This strip is located in the endodermis of plant roots.

2. **Function of the Casparian Strip**: The primary function of the Casparian strip is to regulate the flow of water and minerals into the stele (the central part of the root that contains vascular tissue). It acts as a barrier that prevents passive flow of substances.

3. **Mechanism of Action**: The Casparian strip is impermeable to water and solutes. This means that water and minerals cannot pass through the cell walls of the endodermis cells via the apoplastic pathway (which is the movement through the cell walls and intercellular spaces).

4. **Impact on Water and Mineral Movement**: By blocking the apoplastic pathway, the Casparian strip forces water and minerals to enter the endodermis cells through the symplastic pathway (movement through the cytoplasm via plasmodesmata). This ensures that the plant can selectively absorb the nutrients it needs.

5. **Conclusion**: Therefore, the Casparian strip prevents water and minerals from entering the stele through the apoplastic pathway.

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