Laid end to end, the DNA from all 46 chromosomes of one human cell would measure about:

1. The strand is extraordinarily long compared with its width. 2. If the DNA from all 46 chromosomes in a human cell nucleus was laid out end to end, it would measure approximately two metres. 3. Its diameter, though, would be only 2 nanometres. 4. A typical human cell is about 10 micrometres across, so the DNA must be tightly packaged. _Source: OpenStax Biology for AP(R) Courses (CC BY 4.0), Ch 10 'Cell Reproduction', sections 10.1-10.5_