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Chemistry

The Role of Reactive Oxygen Species in Cellular Signaling Pathways

Quick fact

In low concentrations, reactive oxygen species act as precise cellular signals: they oxidize specific cysteine residues on proteins like tyrosine phosphatases, temporarily switching them off to amplify growth signals—only at high concentrations do they cause damage.

Why this is interesting

You've probably heard that 'free radicals' are harmful molecules that damage our cells. So why do our cells deliberately produce them?