Final Unit: Translation Flashcards
In translation, mRNA is converted to ___
Protein
What are the monomers for proteins?
Amino acids
BACTERIA: How long is the typical polypeptide?
A few hundred amino acids
BACTERIA: Where do ribosomes attach?
At the 5’ ribosomal-binding site
What is the start codon’s code and amino acid it codes for?
AUG, Methionine
What are the stop codons?
UAA, UAG, UGA
What are two other names for the stop codons?
Termination or nonsense codons
What is the role of ribosomes?
Catalyze translation of mRNA into protein
BACTERIA: When do ribosomes begin translating an mRNA?
Before RNA polymerase has finished transcribing it
BACTERIA: When multiple ribosomes attach to an mRNA, what is formed?
Polyribosome
Why is everything more complicated in eukaryotes?
mRNA has to be transported from the nucleus to the cytoplasm
What is tRNA?
An adaptor molecule that delivers amino acids to ribosome
What is the name used for the enzymes that attach tRNA to its correct amino acid?
Amino acyl-tRNA synthetases
How many different Amino acyl-tRNA synthetases are there?
20
What amino acid does tRNA(ser) carry?
Serine
What are three common features of tRNA?
- Cloverleaf structure
- Anticodon
- Acceptor stem for amino acid binding
What is the tRNA anticodon?
It is the opposite of a codon on mRNA. For example, if mRNA has a codon of UCA, then the tRNA anticodon would be AGU.
Although there are 61 different codons, how many tRNAs are there in most cells?
Only about 40
To resolve the difference in codons and tRNAs, Francis Crick proposed the …
Wobble hypothesis
What is the wobble hypothesis?
The third base in codons doesn’t need correct pairing. For example, the anticodon GAG could bind to the codon CUU even though for the third base, G isn’t the correct pairing for U.
What is tRNA with an amino acid attached called?
Aminoacyl tRNA