When our body encounters a pathogen for the first time, the immun… - Vidyadip

Question

When our body encounters a pathogen for the first time, the immune response is generally low, but on exposure to the same pathogen again, the immune response by the body is much more compared to the first exposure. Why is it so?

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Answer

When our body faces a pathogen (like a virus or bacteria) for the first time, our immune system needs time to:
• Identify the invader
• Create specific antibodies
• Build memory cells that remember the pathogen
This first reaction is called the primary immune response, and it’s usually slow and weak.
When the same pathogen enters our body again:
• Our memory B cells quickly produce the correct antibodies
• Our memory T cells help destroy infected cells faster
This is called the secondary immune response, and it’s faster, stronger, and more effective.

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