LECTURE 5 Flashcards
The key translation steps are carried out by _______ since they are responsible for binding the certain three-nucleotide sequence with the appropriate amino acid. Fill in the blank.
tRNA
One type of activating enzyme used during the translation process is called aminoacyl-tRNA synthetase. What is its function?
Brings everything together and allows for translation to occur.
Within your cells, there are similar quantities of aminoacyl-tRNA synthetase and amino acids. What is that number?
20
For three of the sixty-four codons known (shown on your codon chart), there exists no tRNA with a complementary anticodon, these are known as ______________. Fill in the blank.
Nonsense Codons
In prokaryotes and eukaryotes, polypeptide synthesis (translation) begins with the formation of an initiation complex. What components make up this initiation complex?
A special tRNA molecule binding, and initiation factors position tRNA on the ribosomal surface.
What is the abbreviation of the first amino acid placed within prokaryotes within the ribosome to begin the translation process?
MET
Regarding the process of translation, is the function of the initiation factors used during the first process of initiation?
Types of proteins, responsible for positioning tRNA on the surface at the P site
Which statement describes the difference between what occurs at the P, A, and E sites of a ribosome?
P site is where peptide bond forms. A site is where successive amino acid barring tRNA will bind. E site where empty tRNA will exit.
In prokaryotes (and most eukaryotes), the beginning of each mRNA is marked by a ______________ complementary to one of the rRNA molecules on the ribosome, making sure it will be read from the beginning. Fill in the blank.
Leader Sequence
Which statement does not describe a difference between the initiation stage of translation in eukaryotes versus prokaryotes?
Eukaryotic - Occurs on 80S Ribosomes
Prokaryotic - Occurs on 70S Ribosomes
Which statement describes what occurs during the elongation stage of translation in prokaryotes and eukaryotes? (know the different steps we discussed in class with the drawings on the board with the A, P, and E sites)
Amino acid after amino acid at the A site, they’re attaching them to the P site, tha exiting out the E site.
Regarding the process of translation, what is the function of elongation factors?
Assisting binding tRNA to the exposed mRNA codon at the A site
Which statement describes translocation which takes place during the elongation phase of translation?
Taking tRNA attaches it to A site with elongation factors.
Which statement describes what occurs during the termination stage of translation in prokaryotes and eukaryotes?
Occurs when you read one of the stop codons. A release factor will come that will release the newly made polypeptide chain, and then you are finished.
