Mystery #3Tier 2allergies and immunity
Why can one person eat peanuts happily while they make another person dangerously ill?
At a birthday party, one child happily munches a whole handful of peanuts. Another child could become seriously, even dangerously, ill from a single bite of the very same nut. Same peanut, same party, wildly different result. Why are some people allergic to peanuts while others are not?

Your guess
Why do you think peanuts are harmless to one person but dangerous to another?
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