1. The Ribosome –Is part of the cellular machinery for translation, polypeptide synthesis Figure 17.1

2. Evidence from the Study of Metabolic Defects In 1909, British physician Archibald Garrod –Was the first to suggest that genes dictate phenotypes through enzymes that catalyze specific chemical reactions in the cell

3. Nutritional Mutants in Neurospora: Scientific Inquiry Beadle and Tatum causes bread mold to mutate with X-rays –Creating mutants that could not survive on minimal medium; each mutant was defective in a single gene supporting the one gene- one enzyme hypothesis

4. Overview: the roles of transcription and translation in the flow of genetic information No mRNA processing

5. Question : RNA (ribonucleic acid) DNA (deoxyribonucleic acid)How does RNA (ribonucleic acid) differ from DNA (deoxyribonucleic acid)?

6. The triplet code

7. The dictionary of the genetic code

8. The stages of transcription: initiation, elongation, and termination

9. The initiation of transcription at a eukaryotic promoter

10. RNA processing; addition of the 5 cap and poly(A) tail

12. The function of the cap is: –prevent mRNA degradation by hydrolytic enzymes –helps attach to the ribosome Function of the 3’ tail: –same functions as the 5’cap –also helps facilitate export of mRNA from nucleus

13. RNA processing: RNA splicing

14. The roles of snRNPs and spliceosomes in mRNA splicing

15. RNA Splicing Removes noncoding regions called introns snRNPs (small nuclear ribonucleoproteins) recognize the splicing signals that are at the ends of introns The RNA in the snRNP is called snRNA (small nuclear RNA) spliceosomes are the larger protein assemblies formed by the joining of snRNPs

16. Correspondence between exons and protein domains

17. The structure of transfer RNA (tRNA)

19. Translation: the basic concept

20. An aminoacyl-tRNA synthetase joins a specific amino acid to a tRNA

21. The anatomy of a functioning ribosome

22. The initiation of translation

23. The elongation cycle of translation

24. The termination of translation

25. Peptide Bonds Join Amino Acids

26. Polyribosomes

27. Coupled transcription and translation in bacteria

28. The signal mechanism for targeting proteins to the ER

29. The polypeptides of proteins destined for the endomembrane system are marked by a signal peptide, which targets the protein to the ER. A signal recognition particle (SRP) functions as an adaptor that brings the ribosome to a receptor protein built into the ER membrane.

30. The molecular basis of sickle-cell disease: a point mutation

31. Categories and consequences of point mutations: Base-pair substitution

32. Categories and consequences of point mutations: Base-pair insertion or deletion

33. A summary of transcription and translation in a eukaryotic cell