I recently made a video showing how to draw the DNA Helix but I got it wrong! My mistakes were pointed out by Grant Jacobs on his blog

before I drew only eight rungs of the ladder when there should be ten and I had the helix with a left-hand twist wen It should be a right-hand twist. I think I spent so much time thinking how to explain how to draw “a” helix, I didn’t consider that “the” helix had a particular organisation to it. I imagined it springing about coiling and uncoiling in a relaxed sort of way. My appologies if anyone got a D- for their biology homework.

I am more than happy to put this right and hope that this now shows everything properly. Have fun with your bilogy homework!