Scientists have discovered a new property of the molecular motors that shape our chromosomes. While six years ago they found that these so-called SMC motor proteins make long loops in our DNA, they ...

The absence of a nucleus and other membrane-bound organelles differentiates prokaryotes from another class of organisms ... the form of a single molecule, or chromosome, of circular DNA.

Stevens was born July 7, 1861, in Cavendish, Vermont, to a middle-class family that had lived ... made reproductive cells with both X and Y chromosomes whereas the females made only those with ...