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Q1. Due to ___, __ tRNA(s) can pair or hydrogen bond with __ codon(s). Q2. What

ID: 207790 • Letter: Q

Question

Q1. Due to ___, __ tRNA(s) can pair or hydrogen bond with __ codon(s).

Q2. What would we expect to find in an E. coli cell whose environment contains lactose but no glucose?

   Abundant Lac mRNA
   Lactose bound to the repressor protein
   high levels of cAMP
   All the other answers are true.
   CAP/camp activator bound to the promoter of the lac operon.

Q3. How does a ribosome know where to position itself to start translation in a eukaryote?

   It starts to assemble at the 5’cap on the mRNA and starts scanning for AUG.
   It assembles at the first methionine codon
   The 16s rRNA interacts with the Shine-Delgarno site in the 5’UTR
   The TPB binds to the TATA sequence in the promoter.

Q4. in eukaryotes, different proteins can be produce from the same gene by __.

Q5. DNA polymerase I contains _______ activity to _____nucleotides in the Okazaki fragment, and   ____ activity to ____ an incorrectly added nucleotide.

   5'-3' exonuclease, add, 5'-'3' endonuclease, remove
   3'-5' endonuclease, remove, 5'-3' endonuclease, remove
   5'-3' exonuclease, remove, 3'-5' exonuclease, remove
   5'-3 polymerase, remove, 3'-5' exonuclease, remove

Explanation / Answer

Q1: Anticodon, mRNA .

tRNA has anticodns that bonds with codons of mRNA.

Q2:

Q3: It starts to assemble at the 5’cap on the mRNA and starts scanning for AUG.

The cap at the 5 end of eukaryotic mRNA plays a critical role in the initiation of translation. In a series of steps, the small subunit of the eukaryotic ribosome, initiation factors, and the initiator tRNA with its amino acid (Met-tRNAiMet) form an initiation complex that recognizes the cap and binds there. The initiation complex then moves along (scans) the mRNA until it locates the first AUG codon.  

Q4: Alternative splicing.

Q5:

5'-3' exonuclease, add, 5'-'3' endonuclease, remove