1. Today: How do genes work? Discussions begin/began this week.

2. Information flow in cells Protein Fig 15.3

3. Chains of DNA can store information: Fig 4.6,.7 Each chain of DNA is made of individual units = nucleotides

4. Fig 3.8 Proteins are a string of amino acids Proteins are the “doers” of the cell. They act as: Enzymes Structural Support Transporters Signals

5. Tbl 3.3 Amino acids connect together to make proteins.

6. a gene - DNA used to produce RNA or protein The relationship between DNA and genes promotercoding regionterminatornon-gene DNA

7. DNA Composition: In humans: Each cell contains ~6 billion nucleotides of DNA. This DNA is ~2 meters long and 2 nm wide. ~98% does not directly code for amino acids In a single human cell only about 3-5% of genes are expressed at a time.

8. DNA Composition: In humans: Each cell contains ~6 billion base pairs of DNA. This DNA is ~2 meters long and 2 nm wide. ~1.5% directly codes for amino acids ~25% is genes In a single human cell only about 5-10% of genes are expressed at a time.

9. a gene - DNA used to produce RNA or protein The relationship between DNA and genes promotercoding regionterminatornon-gene DNA

10. Five Perspectives about Genes: 1.Genes act as units of heredity 2.Genes are seen as a cause of disease 3.Genes code for proteins 4.Genes act as switches, controlling development 5.Genes are replicators (selfish gene)

11. Fig 14.2 Visualizing the perspectives about genes Different strains of bacteria are injected into mice.

12. Visualizing the perspectives about genes Fig 14.2

13. Visualizing the perspectives about genes

14. Fig 14.2 What has happened to the bacteria? Visualizing the perspectives about genes

15. What part of the cell contains/transfers the information? Fig 14.3

16. Fig 14.2 1.Genes act as units of heredity 2.Genes are seen as a cause of disease 3.Genes code for proteins 4.Genes act as switches, controlling development 5.Genes are replicators (selfish gene) Visualizing the perspectives about genes

17. Fig 14.7 In cells, DNA is a double-stranded helix

18. Five Definitions of Genes: 1.Genes act as units of heredity 2.Genes are seen as a cause of disease 3.Genes code for proteins 4.Genes act as switches, controlling development 5.Genes are replicators (selfish gene)

19. ? 4 nucleotides in DNA 20 amino acids in proteins

20. How can 4 nucleotides code for 20 amino acids? If Ratio (nucleotide:amino acid)Possible combinations 1:14 1 4 Fig 15.6

21. How can 4 nucleotides code for 20 amino acids? If Ratio (nucleotide:amino acid)Possible combinations 1:14 1 4 2:14 2 16 Fig 15.6

22. How can 4 nucleotides code for 20 amino acids? If Ratio (nucleotide:amino acid)Possible combinations 1:14 1 4 2:14 2 16 3:14 3 64 Fig 15.6

23. How can 4 nucleotides code for 20 amino acids? If Ratio (nucleotide:amino acid)Possible combinations 1:14 1 4 2:14 2 16 3:14 3 64 There are more possible combinations than amino acids. Fig 15.6

24. Combinations of 3 nucleotides code for each 1 amino acid in a protein.

25. Fig 15.8 the Genetic Code

26. Changes in DNA can change the protein Fig 16.21

27. Changes in DNA can change the protein Fig 16.21

28. The fat cat ate the rat. change one letter The zat cat ate the rat.

29. The fat cat ate the rat. change one letter The zat cat ate the rat. The atc ata tet her at. delete one letter

30. Combinations of 3 nucleotides code for each 1 amino acid in a protein.

31. Protein How is DNA used to make proteins and RNA? Both proteins and RNA are involved in the processes. Fig 16.10

32. Differences between DNA and RNA Fig 4.1

33. Protein How is DNA used to make proteins and RNA? Both proteins and RNA are involved in the processes. Fig 16.10

34. Genes act as switches. The information in genes is what to make and when to make it. Protein

35. a gene Genes have three basic parts promotercoding regionterminatornon-gene DNA

36. Fig 16.10 Genes contain the information to make RNA and/or proteins. Genes act as switches. The information in genes is what to make and when to make it. Protein

37. 1. Genes act as units of heredity 5. Genes are replicators (selfish gene) For life to exist, the information (genes) must be passed on. Fig 11.1