Seeing Double/Meet Dolly!

cloning

growing a plant or animal from one cell of its parent

Some scientists think that cloning fruits and vegetables can help end world hunger.

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cell

a tiny, basic part of a plant or animal; all living things are made up of cells

You need a strong microscope to see the cell of a bean.

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embryo

an unborn human or animal in the earliest stages of growth

We studied how a chick grows inside an egg, from when it’s an embryo to when it hatches.

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productive

doing or achieving a lot

Antonio was very productive at the library—he finished all his homework.

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breed

mate two animals to produce babies

The zoo plans to breed its Bengal tigers because the species is in danger of dying off.

photo credit: Dmitriy Sylenko/Shutterstock