Resource(s) This activity was adopted and modified from:
DNA RNA Protein Given DNA CTT mRNA GAA tRNA CUU Amino Acid Glu Letter E SAY IT WITH DNA: PROTEIN SYNTHESIS WORKSHEET The Central Dogma states that DNA directs the synthesis of proteins by producing RNA via transcription followed by ribosomal translation of RNA into polypeptides. In this activity, you will decode sequences of DNA into "secret" messages. PART A Determine the “secret” message by transcribing and then translating the bases from the given strands of DNA below (#1-3). Use the dictionary to determine the letter that corresponds to each tRNA codon. You must record ALL your steps from transcription to translation, including the amino acids that correspond to each tRNA codon. For example: If you have done this correctly, the letters should spell out a message in English. DICTIONARY Note: AA = Amino Acid Spc = “space” transcription translation tRNA AA Letter AAA Phe F AAC Leu L AAG Phe F AAU Leu L ACA Cys C ACC Trp W ACG Cys C ACU Thr O AGA Ser S AGC Ser S AGG Ser S AGU Ser S AUA Tyr Y AUC spc - AUG Tyr Y AUU spc - tRNA AA Letter CAA Val V CAC Val V CAG Val V CAU Val V CCA Gly G CCC Gly G CCG Gly G CCU Gly G CGA Ala A CGC Ala A CGG Ala A CGU Ala A CUA Asp D CUC Glu E CUG Asp D CUU Glu E tRNA AA Letter GAA Leu L GAC Leu L GAG Leu L GAU Leu L GCA Arg R GCC Arg R GCG Arg R GCU Arg R GGA Pro P GGC Pro P GGG Pro P GGU Pro P GUA His H GUC Glu Q GUG His H GUU Glu Q tRNA AA Letter UAA Iso I UAC Met M UAG Iso I UAU Iso I UCA Ser S UCC Arg R UCG Ser S UCU Arg R UGA Thr T UGC Thr T UGG Thr T UGU Thr T UUA Asn N UUC Lys K UUG Asn N UUU Lys K
1) DNA : CTA TTA CGA ATC TAG AGC ATT GAA TAG AAA CTT mRNA: tRNA: AA: letter: 2) DNA : TAC ATA ATC TAC TAG TTA CTA ATC TAT AGA ATT TAC CGA CCC TTG TAT mRNA: tRNA : AA: letter: DNA : AAA TAG ACG CTT TTA TGC mRNA: tRNA : AA: letter: 3) DNA : TGA GTG CTT ATT ACG CTC TTA TGC TCC CGC GAG ATC CTA ACT CCC TAC mRNA: tRNA : AA: letter: DNA :CGT ATT TAA TCA ATC ACT TTG ATC TGG GTG CTC ATT TGC CTT AGGTGA mRNA: tRNA : AA: letter: PART B Answer the questions below. 1)Several codons code for “spc”. Explain why this is an advantage or disadvantage for the organism. 2)Are the given strands of DNA from a eukaryotic or prokaryotic organism? Explain your answer. 3) Explain where translation would begin for:
a. DNA sequence #1: CTA TTA CGA ATC TAG AGC ATT GAA TAG AAA CTT b. DNA sequence #3: TGA GTG CTT ATT ACG CTC TTA TGC TCC CGC GAG ATC CTA ACT CCC TAC CGT ATT TAA TCA ATC ACT TTG ATC TGG GTG CTC ATT TGC CTT AGGTGA 4) Construct your own secret DNA message by working backwards in the space provided below (from English AA tRNA mRNA DNA). This message will be handed in on a separate piece of paper with ONLY the DNA sequence on it and then it will be randomly given out to one of your classmates to decode. Keep in mind that the letters B, J, U, X, and Z cannot be used in your message. (CAUTION: obscene or derogatory messages are not acceptable).
You've reached the end of your free preview.
Want to read all 7 pages?