Why are immunoglobulins known as defense proteins ?

Explanation

### Step-by-Step Solution:

1. **Definition of Immunoglobulins**:
- Immunoglobulins, commonly known as antibodies, are specialized proteins produced by the immune system.

2. **Production of Immunoglobulins**:
- These antibodies are formed by B lymphocytes, which are a type of white blood cell (WBC). B lymphocytes differentiate into plasma cells that secrete antibodies into the bloodstream.

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