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which stament is true( more then one can be true)
1) EF-Tu moves the mRNA by one codon
2)EF-G delivers aa-tRNAs to the ribosome
3)Translation initiation occurs by 70S riboosomes binding to mRNAs with fMet-tRNA
4)Translocation refers to the chemical step of peptide bond formation
5)RRF functions to cleave off the peptide chain from the P-site tRNA
6)IF3 is released after the 30S subunit binds mRNA and the fMet-tRNA sits in the P-site; this allows the 50S subunit to bind
I tried 2,6, 1 it was wrong... I tried 2,6 it was wrong , i did 1,3,4 it was wrong, i did 1 and 3 it was wrong i did 2,4,5 it was wrong i did 1 and 2 it was wrong. Now i only have one attempt left Somone one help
To determine which statements are true, let's go through each one and see if we can find the correct answers:
1) EF-Tu moves the mRNA by one codon.
To verify this statement, we need to understand the role of EF-Tu in translation. EF-Tu is responsible for delivering aminoacyl-tRNA molecules to the ribosome during protein synthesis. It does not directly move the mRNA. Therefore, statement 1 is not true.
2) EF-G delivers aa-tRNAs to the ribosome.
To check if this statement is true, we need to understand the role of EF-G. EF-G, also known as elongation factor G, helps in the translocation step of translation. It facilitates the movement of the ribosome along the mRNA. However, it does not deliver aminoacyl-tRNAs to the ribosome. Therefore, statement 2 is not true.
3) Translation initiation occurs by 70S ribosomes binding to mRNAs with fMet-tRNA.
In prokaryotes, translation initiation involves the binding of the 30S ribosome subunit to the mRNA, followed by the binding of the fMet-tRNA to the start codon. The 50S subunit then joins to form a functional 70S ribosome. Therefore, statement 3 is true.
4) Translocation refers to the chemical step of peptide bond formation.
Translocation in translation refers to the movement of the ribosome along the mRNA, not peptide bond formation. Therefore, statement 4 is not true.
5) RRF functions to cleave off the peptide chain from the P-site tRNA.
Ribosome Recycling Factor (RRF) is responsible for dissociating the ribosome from the mRNA and tRNA after translation is complete; however, it does not cleave the peptide chain. Therefore, statement 5 is not true.
6) IF3 is released after the 30S subunit binds mRNA and the fMet-tRNA sits in the P-site; this allows the 50S subunit to bind.
IF3, also known as initiation factor 3, binds to the 30S subunit during the initiation stage of translation. It prevents premature binding of the 50S subunit. Once the mRNA and the fMet-tRNA are properly positioned, IF3 is released, allowing the 50S subunit to bind. Therefore, statement 6 is true.
Based on the explanations above, the correct statements are 3 (Translation initiation occurs by 70S ribosomes binding to mRNAs with fMet-tRNA) and 6 (IF3 is released after the 30S subunit binds mRNA, and the fMet-tRNA sits in the P-site; this allows the 50S subunit to bind).