Chapter 12: Molecular Genetics

1. Chapter 12: Molecular Genetics Bell Ringer: Please name your favorite scientist or contributor to science, and list something that they accomplished

2. Chapter 12 Tentative Itinerary Today - Start 12.1 Tomorrow - Finish 12.1 Thursday 2/20 - 12.1 quiz, start movie Friday 2/21 - finish movie Monday 2/24 - 12.2-12.3 Tuesday 2/25 - coding lab Wednesday 2/26 - 12.2-12.3 quiz, protein lab Thursday 2/27 - start 12.4 Friday 2/28 - finish 12.4, assign review Monday 3/3 - correct chapter review, further review Tuesday 3/4 - Chapter 12 test

3. Griffith • Avery (McCarty an McCluget) • Hershey and Chase • Chargaff • Rosalind Franklin • Watson and Crick

5. Griffith • Avery (McCarty an McCleod) • Hershey and Chase • Chargaff • Rosalind Franklin • Watson and Crick

7. Griffith • Avery (McCarty an McCleod) • Hershey and Chase • Chargaff • Rosalind Franklin • Watson and Crick

9. N P C What makes up DNA? Nucleotides: subunits of nucleic acid, consists of carbon (sugar), phosphate and a nitrogenous base.

10. Erwin Chargaff * There are four different nitrogenous bases in nucleotides * Cytosine, Guanine, Adenine and Thymine * Chargaff analyzed the amount of each in various species of living organisms * Found that the amount of Cytosine is nearly equal to the amount of Guanine *The amount of Thymine is nearly equal to the amount of Adenine *Chargaff’s rule: C=G and T=A

11. Griffith • Avery (McCarty an McCleod) • Hershey and Chase • Chargaff • Rosalind Franklin • Watson and Crick

12. Double Helix- a twisted a ladder shape

13. Griffith • Avery (McCarty an McCleod) • Hershey and Chase • Chargaff • Rosalind Franklin • Watson and Crick

14. Photo 51 + Chargaff’s Rule + some math = Discovering the Structure of DNA

15. purine- double ringed nitrogenous bases; adenine and guanine pyrimidine- single ringed nitrogenous bases; cytosine and thymine/uracil

17. Histone- Group of proteins Nucleosome- DNA wrapped around a histone

18. Griffith • Avery (McCarty and McCleod) • Hershey and Chase • Chargaff • Rosalind Franklin • Watson and Crick

19. semi-conservative replication- proven by John Cairns through autoradiography, parental strands of DNA separate, serve as templates, and produce DNA molecules with one strand of parental DNA and one strand of new DNA 3 Main Stages: I. Unwinding -DNA helicase, enzyme that unwinds and unzips the DNA II. Base Pairing - DNA polymerase, adds nucleotides to the 3’ end - Okazaki fragments = 100-200 nucleotide long strands of DNA which are connected by DNA ligase III. Joining - DNA polymerase removes RNA primers and links the two strands

20. Central Dogma DNA RNA Proteins

21. What is RNA? *DNA = deoxyribose nucleic acid, 2 strands *RNA = ribose nucleic acid, 1 strand *Nucleotide base Thymine in DNA is replaced with Uracil in RNA *Three types of RNA: -Messenger RNA (mRNA) -Ribosomal RNA (rRNA) -Transfer RNA (tRNA)

22. Transcription *The process of synthesizing or creating mRNA from DNA *RNA polymerase is an enzyme that binds to DNA, reads the sequence, and produces an RNA copy of the segment -RNA polymerase I creates rRNA -RNA polymerase II creates mRNA -RNA polymerase III creates tRNA *mRNA is shorter than the strand of DNA it copies -introns = intervening sequences skipped over -exons = sequences from the DNA that remain in the mRNA

23. What is this Code? Codon- three base code in DNA or mRNA Anticodon- three base code that complements a codon, is read 3’ to 5’ Page 338

24. Translation * The creation of a protein from a ribosome translating the mRNA sequence *mRNA travels to a ribosome; to do this, it must leave the nucleus and find a ribosome in the cytoplasm *Ribosome translates the sequence in the mRNA to synthesize a protein

25. Gene Regulation- ability of an organism to control which genes are transcribed in response to changes in the environment operon- a section of DNA that contains genes for the proteins needed for a specific metabolic pathway *operons require an operator, a promoter, a regulatory gene, and the genes coding for proteins trp operon- responsible for transcribing the enzymes necessary for tryptophan synthesis; is repressed when there is tryptophan in the environment, is activated in an absence of tryptophan lac operon- responsible for transcribing the enzymes necessary for lactose digestion; is repressed until an inducer is present to pull the repressor off the promoter

26. Hox Genes

27. Mutations *Occur as mistakes in DNA replication, one base change can have enormous repercussions in the cell/organism * 3 kinds you need to know: -substitutions -frameshifts (insertion/deletions) -duplications

28. Substitutions Missense Mutation- a substitution which leads to the change in charge of the amino acid Nonsense Mutation- a substitution that creates a stop codon in the middle of the sequence Frameshifts Deletions- deletes a base, shifts the codons downward Insertions- inserts a base, shifts the codons upward Duplications Duplication- repeating of a codon Tandem Repeats- repeating of a codon further with every generation

29. THE BIG FAT CAT ATE THE WET RAT *Normal* THB IGF ATC ATA TET HEW ETR AT THE BIZ FAT CAT ATE THE WET RAT THE BIG FAT FAT CAT ATE THE WET RAT THE BIG ZFA TCA TAT ETH EWE TRA THE BIG RAT THE BIG FAT FAT CAT ATE THE WET RAT THE BIG FAT FAT FAT CAT ATE THE WET RAT THE BIG FAT FAT FAT FAT CAT ATE THE WET RAT

30. THE BIG FAT CAT ATE THE WET RAT *Normal* THB IGF ATC ATA TET HEW ETR AT Deletion THE BIZ FAT CAT ATE THE WET RAT Missense THE BIG FAT FAT CAT ATE THE WET RAT Duplication THE BIG ZFA TCA TAT ETH EWE TRA Insertion THE BIG RAT Nonsense THE BIG FAT FAT CAT ATE THE WET RAT THE BIG FAT FAT FAT CAT ATE THE WET RAT THE BIG FAT FAT FAT FAT CAT ATE THE WET RAT Tandem Repeats

31. Mutagens Things that cause mutations