M3 Van- The RNA World

what is the acid in DNA/RNA? why are they called bases?

• acid- the phosphate groups have two hydroxyl groups that can easily donate hydrogens

• bases- the nitrogens in the bases can accept hydrogens

where do the RNA components come from?

• phosphate is a common mineral

• ribose comes from formaldehyde (H2C=O)

• bases come from cyanide (HC=N)

why can RNA fold?

the 2’ OH group (which is missing in DNA) allows hydrogen bonds to form, both as an acceptor and a donor

• this allows a tertiary structure to form

• (the primary structure is the base sequence and the secondary structure is the base pairing )

why is RNA a valid theoretical starting molecule for life?

it can:

• store information- base sequence

• evolve- mutations + selection

• sense the environment- some RNA molecules (riboswitches) can bind to small molecules to detect changes in pH, temp, ions, salts, etc

• catalyse reactions- ribozymes are RNA enzymes

• probably replicate itself (but no real RNA replicase has been created yet)