Chapter 17: RNA, Transcription, Translation Flashcards
What is the central dogma of living things?
DNA –> mRNA –> Protein
What changes are made during transcription?
deoxyribonucleotide –> ribonucleotide
nucleic acid –> amino acid
Why does RNA use uracil?
It’s easier to synthesize. It’s more likely to bind elsewhere but it doesn’t matter because it doesn’t replicate.
What is mRNA?
messenger RNA: single stranded RNA strand. The role of mRNA is to carry protein information from the DNA in a cell’s nucleus to the cell’s cytoplasm (watery interior), where the protein-making machinery reads the mRNA sequence and translates each three-base codon into its corresponding amino acid in a growing protein chain.
What is tRNA?
tRNA: transfer RNA. Transfer RNA serves as a link (or adaptor) between the mRNA molecule and the growing chain of amino acids that make up a protein. Each time an amino acid is added to the chain, a specific tRNA pairs with its complementary sequence on the mRNA molecule, ensuring that the appropriate amino acid is inserted into the protein being synthesized.
What is the promoter in eukaryotic organisms?
TATA Box
What is rRNA?
ribosomal RNA: molecule in cells that is part of the ribosome and that is exported to the cytoplasm to help translate the information in messenger RNA (mRNA) into protein. rRNA are responsible for reading the order of amino acids and linking amino acids together.
What is a promoter?
A non-protein coding sequence which serves as start point for RNA polymerase II. Coding will start after promoter.
What is a transcription factor?
Proteins that stabilize RNA Polymerase II.
What does RNA Polymerase II do?
It plugs in matching nitrogenous bases to the single stranded mRNA, as well as some small nuclear RNA in eukaryotes (snRNA and microRNA).
What is transcription initiation?
The first step of transcription: RNA polymerase binds to promoter, then separates the DNA strands, providing the single-stranded template needed for transcription.
What is transcription elongation?
The second step of transcription: the polymerase builds an RNA molecule out of complementary nucleotides, making a chain that grows from 5’ to 3’, creating a strand identical to the DNA strand with U instead of T
What is transcription termination?
The last step of transcription: Terminator sequences signal that the RNA transcript is complete. Once they are transcribed, they cause the transcript to be released from the RNA polymerase.
What is pre-mRNA?
The first un-processed mRNA strand as a result of transcription. Must be processed (in eukaryotes) into mRNA.
Where does mRNA editing occur?
In the nucleus of eukaryotes
