What are coralloid roots ?

Explanation

**Step-by-Step Solution:**

1. **Definition of Coralloid Roots**: Coralloid roots are specialized roots that differ from typical roots in their structure and growth pattern.

2. **Growth Pattern**: These roots exhibit negative geotropism, meaning they grow upwards, against the force of gravity, similar to how stems grow.

3. **Structure**: Coralloid roots have a unique structure characterized by dichotomous branching. This means that the roots branch out in a way that each branch splits into two, creating a coral-like appearance.

...