What happens in secondary lymphoid organs with respect to immunity?

Explanation

### Step-by-Step Solution

1. **Understanding Secondary Lymphoid Organs**: Secondary lymphoid organs include structures such as lymph nodes, spleen, and mucosal-associated lymphoid tissues (MALT). These organs play a crucial role in the immune response.

2. **Site for Lymphocyte and Antigen Interaction**: The primary function of secondary lymphoid organs is to provide a site where lymphocytes (B cells and T cells) can interact with antigens. Antigens are substances that can provoke an immune response, such as pathogens or foreign molecules.

3. **Activation of Lymphocytes**: When lymphocytes encounter their specific antigen in these organs, they become activated. This activation is essential for the immune response to proceed.

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