Scientists Say

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

  1. Physics

    Scientists Say: Power

    This word describes the rate at which energy is delivered or used to do work, along with related ideas, such as ways of making electricity.

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  2. Animals

    Scientists Say: Species

    This word describes organisms grouped by their similarities in genetics and physical traits. But defining species can be tricky.

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  3. Space

    Scientists Say: Black hole

    This is an object in space with such a strong gravitational pull that nothing, not even light, can escape

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  4. Scientists Say: Hypothesis

    A hypothesis is an idea that scientists propose, then study and explore, to explain phenomena in the natural world.

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  5. Fossils

    Scientists Say: Paleontology

    This is the study of prehistoric life based on fossils of microbes, plants, and animals found in rock.

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  6. Life

    Scientists Say: RNA

    This is a molecule that helps cells make proteins from the instructions encoded in DNA.

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  7. Chemistry

    Scientists Say: Periodic table

    The periodic table is a chart showing all the known chemical elements. An element’s location in the table reveals a lot about its chemistry.

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  8. 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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  9. Materials Science

    Scientists Say: Crystal

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

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  10. 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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  11. 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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  12. 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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