1. transcription DNARNA translation protein Protein Synthesis

2. URACIL (U) base with a single-ring structure phosphate group sugar (ribose)

3. DNA RNA DNA G C A T C G T A G C A U G C T A base-pairing during DNA replication base-pairing during transcription

4. sugar-phosphate backbone of one strand of nucleotides in a DNA double helix sugar-phosphate backbone of the other strand of nucleotides part of the sequence of base-pairs (blue)

5. RNA polymerase, the enzyme that catalyzes transcription DNA

6. transcribed DNA winds up againDNA to be transcribed unwinds newly forming RNA transcript DNA template at the assembly site Transcription

7. 3’ 5’ growing RNA transcript 5’ 3’5’ 3’ direction of transcription Transcription

8. mature mRNA transcript 5’3’ poly-A tail 5’ snipped out ca p transcription into pre-mRNA unit of transcription in a DNA strand exonintronexon intron 3’ 5’

9. base sequence of gene region mRNA From DNA to RNA GATACCAATAACCAC CUAUGGUUAUUGGUG

10. From Codons to Amino Acids CGGGGGUUUUUUUAA arginineglycinetyrosinetryptophantyrosine

12. codon in mRNA anticodon amino acid OH amino-acid attachment site Codon-tRNA-Amino Acid

13. small ribosome subunitlarge ribosome subunit tunnel intact ribosome + Ribosomes

14. mRNA transcript intact ribosome Initiation initiator tRNA small ribosomal subunit

15. binding site for mRNA (first binding site for tRNA) (second binding site for tRNA) platform on small ribosomal subunit

16. Elongation Translation

17. Elongation Translation

18. Termination mRNA new polypeptide chain mRNA

19. original base triplet in a DNA strand During replication, proofreading enzymes make a substitution: a base substitution within the triplet (red) original, unmutated sequence a gene mutation possible outcomes: or

20. mRNA parental DNA amino acids altered mRNA DNA with base insertion altered amino- acid sequence arginineglycinetyrosinetryptophanasparagine arginineglycineleucineglutamateleucine Mutations

21. mRNArRNAtRNA Translation amino acids, tRNAs, ribosomal subunits mRNA transcripts protein subunits ribosomal subunits tRNA Transcription Protein