Why is that in certain plants deficiency symptoms appear first in younger parts of the plant while in others they do so in mature organs?

Explanation

### Step-by-Step Solution:

1. **Understanding Deficiency Symptoms**:
- Deficiency symptoms in plants are morphological changes that indicate a lack of essential nutrients. These symptoms can manifest in different parts of the plant depending on the nutrient's mobility.

2. **Nutrient Mobility**:
- Nutrients can be classified based on their mobility within the plant. Some nutrients are highly mobile, while others are relatively immobile.

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