Transcription and Translation

What is translation?

converting genetic information into proteins, mRNA is code for proteins synthesized at the ribosome

Which are removed from pre-mRNA: introns or exons?

introns

How are amino acids linked?

by peptide chains

What are the several different types of sigma?

...

How many RNA polymerases do bacteria have? Eukaryotes?

1) 1 2) 3

What goes into transcription? What comes out?

1) DNA 2) mRNA

What is an anticodon? Where are they found? How is it related to a codon?

1) a set of 3 ribonucleotides that forms base pairs with the mRNA codon 2) on a loop at the 5' end 3) a anticodon binds to a mRNA codon

What are the 3 steps of the termination of translation?

1) a site encounters a stop codon 2) polypeptide and uncharged tRNA's are released 3) releases bond linking to tRNA to PP chain at P

What is a template strand? A coding strand?

1) a strand of DNA used to synthesize mRNA 2) the other strand and matches the sequence of mRNA

Where does translation take place in a bacterium? A eukaryote?

1) in the ribosome 2) in the cytoplasm

What is RNA splicing? Does it happen in bacteria?

1) introns are removed form the growing RNA strand 2)

What goes into translation? What comes out?

1) mRNA 2) proteins

What are the 3 steps of the initiation of translation?

1) mRNA binds to the small subunit (begins at AUG start codon) 2) the initiatory tRNA binds to the start codon (f-Met) 3) the large subunit binds

What is the structure of the ribosome? What does the small subunit do? What does the large subunit do?

1) proteins and ribosomal RNA 2) holds mRNA in place during translation 3) peptide bonds form

What are ribosomes made of? What is their function?

1) proteins and ribosomal RNA 2) to synthesize proteins

What are the fundamental units of RNA known as? How are they different from the fundamental units of DNA?

1) ribonucleotides 2) ribonucleotides are only found in RNA and it is a different sugar

What are the 3 steps of the elongation of translation?

1) tRNA binds to the A site 2) a peptide bodn forms at the P site 3) translocation : tRNA moves from A to P to E

What 3 steps of translation happen at the ribosome?

1) the amino acid connected to the tRNA enters the A site 2) a peptide bond forms in the P site 3) the ribosome moves 3 bases and the tRNA exits the E site

What is an exon? Intron?

1) the regions of eukaryotic genes that are part of the final mRNA 2) the sections of genes that are not in the final RNA product

There are 5 steps of the initiation of transcription. What are they (in order)?

1) the sigma opens the DNA double helix 2) the template strand is threaded through RNA polymerase 3) incoming NTP's pair with complementary bases of DNA's template strand 4) RNA polymerization begins 5) the sigma disonnects after initiation began

What is tRNA? What does it do? How is it different than mRNA?

1) transfer RNA 2) transfers amino acids from the RNA to a growing polypeptide 3) mRNA codes for a specific amino acid

What is pre-mRNA? What needs to be changed for it to be a functional molecule?

1) when the eukaryotic genes of any type are transcribed 2) eukaryotic cells must dispose of certain sequences inside the primary transcript and then combine the seperated sections into an integrated whole

What direction is mRNA formed?

5' to 3'

How is the RNA process different in eukaryotes vs. bacteria?

In bacteria, DNA is converted to mRNA directly. In eukaryotes, transcription produces pre-mRNA, immature, before translation it requires another step

How is translation at the ribosomes different for bacterial and eukaryotes?

In bacteria, polyribosomes form, which means that ribosomes attach to mRNA's and begin synthesizing proteins before transcription is complete. In eukaryotes, primary transcripts are processed in the nucleus to produce a mature mRNA, then exported to the cytoplasm.

What enzyme is working during the elongation phase of transcription?

RNA polymerase

What enzyme synthesizes mRNA?

RNA polymerase

How does the termination phase of transcription occur?

RNA polymerase encounters a transcription termination signal in DNA

What is a sigma? How is it related to the RNA polymerase?

a protein subunit, that guides RNA polymerase to the DNA template strand

What is required for transcription to begin?

a sigma

What are the bonds between RNA called?

phosphodiester bonds

Unlike DNA polymerase, RNA polymerase does not require a _______ before transcription.

primer

What is rRNA?

ribosomal RNA

What is transcription?

the synthesis of mRNA from DNA