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Why can tattoo ink outlast the cells holding it?

Tattoo pigment can remain in place even when the cells carrying it are replaced. In a study using green pigment in mouse skin, researchers found evidence of release and recapture by dermal macrophages. The model offers a reason lasting color need not mean a single cell lasts as long as the tattoo.

4–6 min

Questions you could explore

  • What would need checking before extending this explanation to every human tattoo ink?

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Health and the body

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3–5 min

How does daylight set the body’s clock?

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How does a vaccine give the immune system a memory?

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4–5 min

How does a vaccine give the immune system a memory?

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Health and the body

Why won’t an antibiotic treat a viral cold?

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2–3 min

Why won’t an antibiotic treat a viral cold?

Health and the body2–3 minThe word infection covers illnesses caused by very different organisms. An antibiotic that helps against certain bacteria has no matching target in the viruses that cause a cold.

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