Drawing DNA & RNA Nucleotides & DNA Double Helix
Drawing simple diagrams of the structure of single nucleotides of DNA and RNA
- Simple shapes can be used to draw the main building blocks of nucleotides and the DNA double helix
- Advanced drawing skills are not required!
- Pentagons can represent pentose sugars
- Circles can represent phosphates
- Often shown as a circle with the letter P inside: ℗
- Rectangles can represent bases
- Covalent bonds can be shown with solid lines
- Hydrogen bonds can be shown with dashed lines
- Or with complementary shapes that fit together (see diagrams)
Simple shapes can be used to represent parts of nucleotide molecules
Two nucleotides shown bonded together covalently within a strand
When drawing the base pairing, the opposite strand should be antiparallel to the first. The presence of hydrogen bonding is shown, but the numbers/lengths of bonds is not required
An alternative way to draw a DNA strand is to use complementary shapes for the bases
Examiner Tip
Simple, hand-drawn shapes will suffice in an exam. Expert tip - a large drawing is always easier for an examiner to read (and award marks for) than a small one!Read the question carefully; examiners often want a whole nucleotide to be identified in your diagram and to ensure your diagram includes all 4 complementary bases.You don't have to remember the number of hydrogen bonds between the bases.Also, remember to draw DNA strands as antiparallel (one upside-down versus the other) but you don't have to be able to draw a helix shape!
