Scientists Say

A weekly word defined, in a sentence and in context.

  1. Health & Medicine

    Scientists Say: Lymph

    Lymph is a colorless fluid that bathes the body’s tissues and mops up bacteria, viruses and wastes.

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  2. Materials Science

    Scientists Say: Crystal

    The atoms or molecules in crystals take on a particular, repeatable pattern.

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  3. Archaeology

    Scientists Say: Mummy

    Mummies are dead bodies that don’t rot. They can form under natural conditions or because of chemicals that stop decay.

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  4. Life

    Scientists Say: Zooxanthellae

    Algae called zooxanthellae live in the tissue of coral and provide the coral with food and its color.

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  5. Space

    Scientists Say: Galaxy

    A galaxy is a group of millions to billions of stars, plus a lot of dust and gas.

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  6. Animals

    Scientists Say: Extinction

    When the last member of a species dies, it’s gone forever. That species is extinct.

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  7. Chemistry

    Scientists Say: pH

    pH is a scale used to measure the acidity or alkalinity of a solution. The scale ranges from zero to 14, with seven as the perfect neutral middle.

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  8. Scientists Say: Mineral

    Minerals are chemical elements or compounds that form repeating crystal structures. Quartz is a mineral. Table salt is, too.

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  9. Health & Medicine

    Scientists Say: Olfactory

    Smell something? Thank your olfactory sense. Olfactory refers to anything having to do with smell.

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  10. Animals

    Scientists Say: Hertz

    Frequency is how often something repeats over a period of time. Frequency is often measured in hertz, the number of times a cycle repeats each second.

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  11. Physics

    Scientists Say: Big Bang

    The Big Bang is the current theory about how our universe came to be. It began with a vast explosion of matter — a very Big Bang.

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  12. Life

    Scientists Say: Mitosis

    Mitosis is a type of cell division where one cell divides into two identical copies, called daughter cells.

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