Scientists Say

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

  1. Earth

    Scientists Say: Upwelling

    This is a process in which a substance rises and spreads out over something else. Upwelling happens in the ocean, inside the Earth and even in a planet’s atmosphere.

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  2. Animals

    Scientists Say: Krill

    Krill are small crustaceans in the ocean. They are an important food source for other larger animals, and their tiny swimming motions can mix nutrients in the sea.

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  3. Genetics

    Scientists Say: Intron

    These are sections of DNA that are trimmed out before the DNA is copied RNA and translated into protein. But they still have important jobs to do.

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  4. Space

    Scientists Say: Nebula

    Nebulae are huge dust clouds in space. Some come from dying stars. Others are places where stars are born.

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  5. Health & Medicine

    Scientists Say: Melatonin

    Levels of this hormone rise at night when we are asleep and drop during the day. This helps to control when we sleep and wake up.

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  6. Animals

    Scientists Say: Kakapo

    This is a flightless parrot that lives in New Zealand. Unfortunately, there are only 154 of them left.

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  7. Earth

    Scientists Say: Stratigraphy

    Stratigraphy is a branch of geology that looks at how rock layers are organized to understand how the world has changed over time.

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  8. Tech

    Scientists Say: Engineering

    Want to build a bridge, clean dirty water, make a new drug or build a machine? You’re going to need an engineer — someone who uses science and math to solve practical problems.

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  9. Health & Medicine

    Scientists Say: Ultrasound

    Ultrasound is a word used to describe any sounds higher than a person can hear. It’s also a technique used to see inside the body.

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  10. Environment

    Scientists Say: Runoff

    Water that flows through soil and into rivers, lakes and oceans becomes runoff. That runoff can carry part of the land — including its pollution — to the sea.

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  11. Life

    Scientists Say: Vacuole

    Cells can’t always get rid of trash or digest food immediately. This week’s word describes where they store their stuff.

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  12. Plants

    Scientists Say: Invasive species

    These are foreign species that are causing problems for native organisms and ecosystems.

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