Cells cram DNA into the nucleus in two distinct ways
Some chromosomes look like crumpled balls while others resemble flat sheets of paper, heat maps show

Cramming meters-long DNA strands into a cell’s tiny nucleus is an astonishing feat. A new study suggests that cells from plants (shown), animals and fungi accomplish it one of two ways.
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There are only so many ways to cram DNA into a cell’s nucleus, a study suggests.