QUESTION 17 Which of the following best supports the idea that the genetic code is composed of triplet codons? O A. Poly G RNA directs synthesis of poly glycine B. Addition or deletion of one base in a coding region causes an abnormal, defective protein to be produced. OC. Poly U RNA directs synthesis of poly proline. O D. Addition or deletion of three bases in a coding region can result in the production of a protein that s retains normal function. O E. A and C are both correct.

Question 1: tRNA and amino acyl tRNA synthetases Part a:  How many codons encode the amino acid Isoleucine (Ile, I)? Part b: How many codons encode the amino acid Valine (Val, V)? Part c: How many codons encode the amino acid Methionine (Met, M)? Part d: How many tRNAs decode the Ile codons? Part e:  How many tRNAs decode the Val codons? Part f: How many tRNAs decode the Met codon?

QUESTION 16 CRISPR in nature evolved as a "bacterial immune system" or "genetic vaccine" to target infecting viruses. What aspect of the system can we now manipulate so that you can promote *more* transcription of a desired gene? O A nuclease deficient cas9 a single amino acid mutation in Cas9 o edit the PAM sequence supply a DNA template with the cas9/guide RNA use a special guide RNA

Question 12 What is the purpose of the inverted repeats at the ends of DNA-based transposons? A. The inverted repeats are recognized by restriction enzymes that cut out the transposon B. The inverted repeats are magnets for nucleases C. The inverted repeats are the sites of transfer on the target RNA D. The inverted repeats are recognized and cut by transposase to move the transposon from its original location

QUESTION 11 Which of the following statements about RNA interference pathways and mechanisms is FALSE? O A Investigators can load RISC and/or RITS complexes with artificial, designed RNAS in order to specifically target and silence a gene of interest as a way to see what the effect of that gene is when its expression is silenced. O B. Only a small section of a small interfering RNA, called the 'seed' sequence, is actually used to identify nucleic acid targets that are to be silenced. OC. Eukaryotic RNA interference pathways do not regulate genes from the genome itself (i.e. endogenous genes), they only respond to external infection events such as invading viruses. The piRNA pathway processes small RNAS out of long noncoding RNA transcripts and is important for suppression of repetitive element movement in germ cells. OD. O E. The micro (n RNA pathway and the short interfering (si) pathways load small RNAS into RISC or RITS complexes.

Question 10. A mRNA contains a codon with the sequence 5'-GAA-3'. Answer A and B for credit. A. What amino acid is encoded by this codon? B. What would be the most likely sequence of the anticodon in the tRNA that recognizes it? Write your answer starting with the 5' end and include 5' and 3' in your answer to get credit.

Before the next elongation cycle can take place at a ribosome, the peptide chain of the peptidyl-tRNA has to be transferred to the ___ site and the deacylated tRNA has to move to the ___site.   Question 46 options:   A, P   P, A   A, E   P, E   there is no peptidyl transfer happening during protein translation

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Question 6 of 10 can determine how an organism's The presence or absence of a single body works or how a cell does its tasks. O A. TRNA O B. ribosome O C. RNA O D. protein SUBMIT PREVIOUS

Question 7: At third codon positions, approximately what proportion of muations are synonymous? A. None B. 4% C.30% D. 70%