The chief sinks for the minerals elements are the ------------ regions of the plant.

Explanation

**Step-by-Step Text Solution:**

1. **Understanding the Terms:**
- In plant physiology, the terms "source" and "sink" are used to describe where substances are produced and where they are utilized, respectively.
- The source is typically where substances like food or water are generated, while the sink is where these substances are consumed or needed.

2. **Identifying the Source:**
- The primary source of organic substances (like sugars) in a plant is the leaves, where photosynthesis occurs.
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