All Flashcards
What happens when the ribosome reaches a stop codon?
Translation terminates, the release factor binds, and the polypeptide is released.
What is the effect of reverse transcriptase on a retrovirus?
It allows the retrovirus to convert its RNA genome into DNA, which can then integrate into the host cell's genome.
What is the effect of a mutation in the start codon?
Translation may not initiate correctly, leading to a non-functional or truncated protein.
What is the effect of inhibiting tRNA function?
Protein synthesis is halted because amino acids cannot be delivered to the ribosome.
What happens when a release factor binds to the stop codon?
The polypeptide is released from the ribosome, and translation terminates.
What are the three main steps of translation?
Initiation, Elongation, Termination
What are the key events in the initiation of translation?
Ribosome binds to mRNA at the start codon (usually AUG), initiator tRNA and ribosomal subunits bind, tRNA is positioned at the P site.
What are the key events in the elongation stage of translation?
tRNA brings the correct amino acid to the A site, peptide bond formation, translocation of the ribosome.
What are the key events in the termination stage of translation?
Ribosome reaches a stop codon, release factor binds, polypeptide is released, ribosome disassembles.
What are the steps of retroviral replication?
Reverse transcription of RNA to DNA, integration of viral DNA into host genome, transcription of viral DNA into RNA, translation of RNA into viral proteins.
What is the definition of Translation?
The process where the genetic code in mRNA is used to build a polypeptide on ribosomes.
What is a codon?
A three-nucleotide sequence on mRNA that specifies an amino acid.
What is a ribosome?
A complex molecular machine that synthesizes proteins.
What is tRNA?
Transfer RNA; it brings the correct amino acid to the ribosome based on the mRNA codon.
What is a release factor?
A protein that binds to a stop codon, causing the polypeptide to be released from the ribosome.
What is reverse transcriptase?
An enzyme used by retroviruses to convert RNA into DNA.