Table of Contents The Genetic Code How Cells Make Proteins Mutations

1. DNA: The Code of Life Table of Contents The Genetic Code How Cells Make Proteins Mutations

2. Which picture matches the vocab word? • Nitrogen bases • DNA replication

3. What forms the genetic code? • DNA = sides are made of sugar, “rungs” are made of nitrogen bases, A, T, G, C

4. What forms the genetic code? • DNA STRUCTURE • DRAW IN NOTES: • Double Helix shape • nitrogen bases • ( (adenine, thymine guanine, cytosine) • Sugar sides

5. What forms the genetic code? • The order of nitrogen bases along a gene forms a genetic code that specifies what type of protein will be produced

6. Gene Deoxyribose (a sugar) Gene Chromosome Thymine Guanine Cytosine Adenine Phosphate What forms the genetic code? A gene is a section of DNA Genes are made of many nitrogen bases (hundreds to millions) they code for one protein *Remember: proteins make up everything!

7. What forms the genetic code? • 3 nitrogen bases are the code for 1 amino acid • A chain of amino acids make proteins (like a pearl necklace) • Genes are “on” or “off,” make or don’t make a protein

8. How does DNA copy itself? • DNA replicates, or makes an exact copy of itself

9. How does DNA copy itself? Starts with part of the DNA unwinding, nitrogen bases “unzip” and separate New nitrogen bases match up with the “unzipped” bases

10. How does DNA copy itself? • A always pairs with T (adenine with thymine) • G always pairs with C (guanine with cytosine) • This way, the replicated DNA is always the same as the original DNA • Online assignment

11. 3.2

12. Which picture best matches the vocab word? • Messenger RNA • Transfer RNA

13. Where does a cell make proteins? • Start – nucleus • The “code” carried to the cytoplasm • Protein is made in the ribosomes (little dots)/cytoplasm Ribosome

15. How does a cell make proteins? • During protein synthesis, the cell uses information on a gene to make a specific protein

16. How Cells Make Proteins Proteins are made of little chains of amino acids There are 20 kinds of amino acids

17. How does a cell make proteins? • Proteins are made in the cytoplasm with RNA • RNA = similar to DNA but contains A G C U • (adenine, guanine, cytosine, uracil) • A to U • G to C

18. How does a cell make proteins? • mRNA copies the DNA in the nucleus, brings to ribosome in cytoplasm • tRNA carries amino acids to the ribosome to make a chain of protein

24. How Cells Make Proteins Protein Synthesis Chart

25. Online animation • http://www.youtube.com/watch?v=erOP76_qLWA&feature=related

26. 3.3

27. How can mutations affect an organism? • Mutation = any change in DNA or base sequence • Mutations cause an incorrect protein to be made • So, traits may be different from normal!

28. How can mutations affect an organism? 3 types of mutations: Deletion – base pair is removed Addition – base pair is added Substitution – one base pair is switched for another

29. How can mutations affect an organism? • Mutations can be helpful, harmful, or neither • Brainstorm Examples: • Helpful • Harmful • Neither

30. How is cancer related to mutations and the cell cycle? • Cancer begins in the cell cycle, when DNA mutation causes the cell to divide uncontrollably

31. Mutations Cancer Cell

32. How is cancer related to mutations and the cell cycle? • Cancer = cells divide uncontrollably • tumor = a mass of abnormal cells • Cancer can spread through the blood stream

33. Mutations Cancer Cell

34. Mutations Cancer Cell

35. How is cancer related to mutations and the cell cycle? • Doctors use chemotherapy, surgery, or drugs to treat cancer • Chemotherapy – drugs or radiation to destroy cancerous cells • -can destroy healthy cells too

36. Mutations video • http://www.youtube.com/watch?v=2ZRYp5kRFfI&feature=related