RNA world Flashcards
what is the RNA world hypothesis?
where self-replicating RNA molecules proliferated before the evolution of DNA and proteins.
What is the Octet rule?
atoms full their valence shell by
- sharing electrons
OR
- donating/accepting electrons
How many covalent bonds doe CHNOPS preferentially form?
H 1 C 4 N 3 O 2 S 2 P 5
What is electronegitivity?
The ability for an atom to attract shared electrons.
similar electronegtivity = non-polar
How do nucleotide monomers link?
5’-3’ phosphodiester bond
Which is the first carbon in a nucleotide sugar?
The one bonded to the base
How do we name nucleoSIDES?
Andenosine Guanosine Uridine Cytidine Thymidine
Which bases are purines?
Two rings:
Adenine
Guanine
Which bases are Pryimidines?
One ring:
Cytosine
Uracil
What direction is RNA made and read from?
5’ to 3’
How do DNA nucleotides and RNA nucleotides differ
RNA has an extra 2’ hydroxyl group
- so can from 2 hydrogen bonds
- so it can fold
What are the capacities of RNA?
- Stores information
- Adapt/mutate (chemical reactions that cause base change)
- Sense the environment (e.g. glutamine riboswitches, change in response to temp, pH, salt conc etc)
- catalyse reactions
- self replicate
What are some relics of the RNA world?
- Cofactors (ATP, FAD, CoA, NAD)
- Ribosomes