Question

what is the name of the structures that are built to recognize specific invaders and trigger an immune response? antigens macrophages antibodies

Explanation:

To solve this, we analyze each option:

• Antigens: These are substances (invaders or parts of them) that trigger an immune response, not the structures that recognize.
• Macrophages: They are immune cells that engulf and digest invaders, not primarily for specific recognition to trigger response.
• Antibodies: These are Y - shaped proteins (structures) produced by B - cells. They recognize specific antigens (invaders) and trigger an immune response like neutralizing the invader or marking it for destruction.

Answer:

antibodies