DNA to RNA to Protein Flashcards
what is the purpose of RNA as an intermediary
allows for genes to be expressed with different efficiencies
what are the differences between RNA and DNA
- ribose vs deoxyribose sugars
- uracil vs thymine
what is the purpose of the template strand
to be used for transcription
what is the purpose of the coding strand
to provide sequence of the final product
what does RNA polymerase do
transcribes DNA to RNA
what are the characteristics of RNA polymerase
- catalysis of ribonucleotide linkage
- doesn’t need primer
- makes more mistakes than DNA polymerase b/c it lacks exonuclease activity
what are the types of RNA made by cells
mRNA, rRNA, tRNA
what are the steps in transcription
binding, initiation, elongation, termination
what are the next steps for mRNA
- must leave nucleus for translation
- exits thru nuclear pores
what are the mechanisms of mRNA processing
RNA capping and polyadenylation
describe RNA capping
- methylated guanosine (guanine attached to ribose ring) added to 5’ end
- allows ribosome to bind mRNA
describe polyadenylation
series of adenine nucleotides added to 3’ end
what is the purpose of eukaryotic mRNA processing
to increase the stability of mRNA and indicates transcript is ready for translation
describe exons vs introns
exons are coding sequences, whereas introns are noncoding sequences
define spliceosomes
complex of proteins and RNA molecules that splice RNA