1. DNA, RNA, & Protein Synthesis Chapter 10

3. KEY PLAYERS Watson-Crick Rosalind Franklin

4. WATSON & CRICK Noble prize for discovering DNA structure

5. ROSALIND FRANKLIN X-Ray diffraction photos essential in identifying DNA structure Identified the phosphate and sugars located on outside, bases on inside

6. DNA

7. STRUCTURE OF DNA DNA consists of 2 long strands made up of nucleotides Nucleotide is made up of 3 parts

8. NUCLEOTIDE Sugar Phosphate Nitrogen Base Adenine (A) - - Thymine (T) Guanine (G) - - Cytosine (C)

11. 2 CLASSES OF NITROGEN BASES Purines Pyrimidines

12. PURINES 2 rings of carbon AdenineGuanine

13. PYRIMIDINES 1 ring of carbon CytosineThymine

14. DNA STRUCTURE Two strands bonded together then twist (aka double helix) Called a ladder Strands are held together in middle by weak hydrogen bonds

16. Complementary Base Pairing Nitrogen bases MUST bond in specific pairing Base-pairing rule: Adenine always bonds with Thymine Guanine always bonds with Cytosine

18. DNA REPLICATION DNA makes a copy of itself DNA helicase Enzyme that breaks H+ bond Replication Fork Point where 2 chains separate

19. DNA REPLICATION As site opens up, complimentary bases of nucleotides attach to open sites DNA Polymerase Enzyme that attaches nucleotide to form new strand

21. DNA REPLICATION Replication MUST occur simultaneously at many sites along the DNA strand If it were to start at one end and move to the other it would take 16 days to copy one DNA molecule of a fruit fly

22. DNA TRIVIA Done in 3 minutes starting at 6000 different sites 50 nucleotides added per second

25. RNA

26. Needed for protein synthesis Uses DNA as a template for this process

27. RNA STRUCTURE 3 major differences between DNA & RNA DNARNA 1. Double strand vs.Single strand 2. Deoxyribosevs. Ribose 3. Thyminevs. Uracil

29. TYPES OF RNA Messenger RNA (mRNA) Created first in transcription Code (message) from DNA

30. TYPES OF RNA Transfer RNA (tRNA) Looks like a “T” Picks up the amino acid transfers to ribosome

32. TYPES OF RNA Ribosomal RNA (rRNA) Globular (globby) Used to assemble ribosomes

33. PROTEIN SYNTHESIS

34. TRANSCRIPTION RNA polymerase binds to DNA causing the two strands to separate Promoter Terminal Signal

35. TRANSCRIPTION All types of RNA are produced this way DNA forms the code to make RNA mRNA carries message out to cytoplasm

38. PROTEIN SYNTHESIS 20 amino acids are available for the synthesis of proteins Several RNA codes are used for each amino acid

39. CODONS Three sequential bases on mRNA Codon codes for specific amino acid, start, or stop signal

40. CODONS AUG acts as start codon tells translation where should start UGA, UAA, and UAG tell to stop tells translation where to end

41. TRANSLATION Making polypeptides (proteins) from information on mRNA Codon is matched up with anticodon which is picked up by tRNA

42. TRANSLATION tRNA “opposite” to mRNA tRNA anticodons pair with corresponding mRNA codons → amino acids join → polypeptide form

46. HUMAN GENOME PROJECT Have entire gene sequence of human DNA Know the order of 3.2 billion base pairs of 30,000 genes on the 23 chromosomes Now, we just have to figure out what it means…

47. MUTATIONS & MUTAGENS

48. MUTATION Any change in the DNA nucleotide sequence Can involve large regions of a chromosome or just a single nucleotide base pair Can be good, bad, or indifferent

50. 3 TYPES OF MUTATIONS Base substitution Nucleotide deletion Nucleotide insertion

52. DNA REPLICATION DNA very accurate in replication process Repair enzymes - “proofread” & fix mistakes keeping errors to 1:billion That would be like typing your textbook about 1,000x and making only a single mistake

53. MUTAGENS A chemical or physical agent that causes a mutation Physical – high-energy radiation Chemical – drugs Carcinogens – cause cancer