DNA structures

Scale, proportion, and quantity belong to one of the cross cutting concepts in the next generation science standards (NGSS). According to Volume 2 of the NGSS, "in engineering, no structure could be conceived much less constructed without the engineer's precise sense of scale." The authors go on to note that scale and proportion are best understood using the scientific practice of working with models. Read more

April 25th (4/25) is national DNA day. Digital World Biology™ celebrates by sharing some of our favorite DNA structures. We created these photos with Molecule World™ Molecule World is a tools for exploring molecular and chemical structures on an iPhone or iPad. Read more

by Sandra Porter


If you've seen our blog posts about different forms of DNA (A, B, Z), nucleosomes, telomeres, or DNA sequencing, you might get the idea that we're a bit obsessed with DNA. And, you'd be right. We find DNA to be amazingly fascinating and beautiful, as well.


That fascination and sense of wonder inspired us to devote our ... Read more

A key concept in science is molecular scale. DNA is a fascinating molecule in this regard.

While we cannot "see" DNA molecules without the aid of advanced technology, a full length DNA molecule can be very long. In human cells, other than sperm and eggs, six billion base pairs of DNA are packaged into 22 pairs of chromosomes, plus two sex chromosomes. Each base pair is 34 angstroms in length (.34 nanometers, or ~0.3 billionths of a meter), so six billion base pairs (all chromosomes laid out head to toe) form a chain that's two-meters long. If we could hang this DNA chain from a hook ... Read more

by Todd Smith


A key concept in science is molecular scale. DNA is a fascinating molecule in this regard.


While we cannot "see" DNA molecules without the aid of advanced technology, a full length DNA molecule can be very long. In human cells, other than sperm and eggs, six billion base pairs of DNA are packaged into 22 pairs of chromosomes, plus two sex chromosomes. Each base pair is 34 angstroms in length (.34 nanometers, or ~0.3 billionths of a meter), so six billion base pairs (all chromosomes laid ... Read more