When the adventitious roots have swollen regions at frequent intervals, it is called.............

Explanation

**Step-by-Step Solution:**

1. **Understanding Adventitious Roots**: Adventitious roots are roots that arise from parts of the plant other than the main root (taproot). They can develop from stems or leaves and serve various functions, including support and nutrient absorption.

2. **Identifying Swollen Regions**: The question specifies that these adventitious roots have swollen regions at frequent intervals. These swollen parts are typically involved in storing nutrients or water.

3. **Naming the Type of Roots**: The swollen regions on adventitious roots are characteristic of a specific type of root. When these roots have swollen areas, they are referred to as "Fasciculated roots."

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