MediumScience
"I am an invisible army that fights for you every moment of every day. I remember every enemy I have ever defeated. I can be defeated by things too small to see. What am I?"
Answer
The Immune System
Explanation
The immune system is a complex network of cells and proteins that defends the body against infection. Immune memory cells remember past pathogens — which is how vaccines work. Viruses and bacteria are far too small to see yet can overwhelm the immune system.
This is a medium riddle in the Science category — Riddles about physics, space, biology and the laws of the universe.
Tags:bodyscienceclassic
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