Explore the pairing of bases
The first three exercises are overview and skills
| Title | Brief description | Clickable |
|---|---|---|
| Why DNA strands pair | What 'complementary' really means | Launch |
| Compare pairs | Visualize specific strand matching | Launch |
| Assign partial charges | The bases interact through the partial (+) and (-) on their faces. Can you I.D. them? | Launch |
| Explore GC | What must be done to orient cytosine to 'match' with guanine? | Launch |
| AT paired up | Pre-rolled Ade-Thy all matched up | Launch |
| AU paired up | Pre-rolled Ade-Ura all matched up | Launch |
| AC No go | NON-pairing is just as important. Look at Ade-Cyt | Launch |
| GT No go... but! | G and T face off poorly... but can you help them find a way (it happens in wobble!) | Launch |
| GU No go... but! | G and U face off poorly... but can you help them find a way (it happens in wobble!) | Launch |
| Snap out of it | Several of the bases have 'tautomers'--forms they visit. What changes when G tautomerizes? | Launch |
| Gua's tautomer | When Gua is in its tautomeric form... how does the coupling with Ura go? | Launch |
| Cyt's tautomer | When Cyt is in its tautomeric form... how does the coupling with Gua go? | Launch |
| Uh-oh: water vs. Cyt | Several of the bases can 'deaminate'; when cytosine does, it become...uracil! | Launch |
| Bad boy hypoxanthine | Water turns adenine to the darks side--it's now hypoxanthine" | Launch |
| Who do you love? | In adenine's 'Mr. Hyde' state, what partner does it prefer? | Launch |
| How does T differ from U? | DNA uses thymine; RNA uses uracil. Is the difference basepairing? (answer) | Launch |
| What if we allow some 'wobbling'? | Crick pointed out that more pairings were possible if the bases could 'slide' relative to each other... and as he suggested, this allowed for economies in tRNA production. Examine hypoxanthine's pairing with C, U, A (G:T pairing can be explored above | Launch |