Mention two common characters shared by all gymnosperms.

Explanation

### Step-by-Step Solution:

1. **Identify the Group**: We are discussing gymnosperms, which are a group of seed-producing plants.

2. **Characteristic 1**: One common characteristic of all gymnosperms is that they **lack a protective outer covering around their seeds**. This means that their seeds are exposed and not enclosed in a fruit.

3. **Characteristic 2**: Another common characteristic is that gymnosperms **do not produce flowers or fruits**. Instead of flowers, they typically have cones (strobili) where the reproductive structures are located.

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