1. Mistakes can occur in any process. When do mistakes have stronger effects – When making a DNA? Making mRNA? Making a protein? Explain why. (Same as saying - in the encyclopedia, in the transcript, in the student’s homework) Journal 2 11.16.11

2. All of the cells in our body contain exactly the same DNA set. So, how is it possible that cells of the liver differ from muscle cells (or other)? Explain according to what you know so far about gene expression. Journal 1 11.16.11

4. 1)When reading the genetic code, all the way to the ‘protein’, what kind of mistakes did you make, or could have made? 2) What would be the effect of such mistakes on the resulting protein (or word)?

5. Central Dogma Song “DNA Damage”

6. DNA is under constant attack from reactive chemicals and natural background radiation. Free radicals are the byproducts of normal metabolism in human cells. Seen here as bright particles they sometimes react with DNA and cause chemical changes. Radiation can also affect DNA. For example ultraviolet light from the sun can cause harmful chemical changes in the DNA of skin. These changes can lead to kinks in the DNA that prevent genes from being correctly read or deletions that alter the type of proteins produced. Thanks to constant biochemical repair work most mutations are corrected before that have any effect. But in rare cases mutations can accumulate and this can give rise to diseases such as cancer.

8. 1) What is a mutation? Answer as best you can. 2) Watch the video “DNA damage”. - What are conditions that can damage the DNA and lead to errors in the nucleotide sequence? 3) Write one more important fact, or question, based on this videoclip.

9. What will be the effect of a substitution on the resulting protein? Let’s examine and see! (Materials needed: Genetic Code Table)

10. If the normal Gene is: TACTTACCTTATACGATC. What would happen to the new protein if the following point mutations occurred? 1. 2 nd T substituted with G. 2. Last G Substituted with T 3. 4 th T substituted with G 4. 2 nd C was deleted 5. One C inserted after 3 rd T.

11. Mutation Number: Amino acid Sequence: Mutation Effect: normal M-A-G-I-C---------

12. In conclusion: Mutations 1.Mutations are random damages to the DNA, that can be induced by chemicals and radiation. 2.Mutations can have a small, or large, or no effect on the protein. 3.Mutations can have a negative, positive or no effect on the organism. 4.Mutations may or may not be inherited!

13. Point Mutations - When one nucleotide is changed. 1. Substitution (replacement) 2. Deletion (one nucleotide missing) 3. Insertion (one nucleotide added) Notes

14. Substitutions might: 1) Change one amino acid (which may or may not affect the protein’s function) 2) Cause an EARLY STOP, canceling the entire protein. 3) Have NO EFFECT! (3 rd base)

15. Deletion and Insertions cause a SHIFT in the READING FRAME: All the amino acids further from the mutation are changed. Notes

16. Where in the body are mutations more effective?

17. Germ Cells versus body Cells Normal cell: Mutated Cell: Germ Cells: Body Cells:

18. Possible Local Effect Does not pass on to the offspring

19. or Fertilized egg Entire Offspring Might be Affected Mutation is Inherited!

20. A mutation is meaningful if: 1) It affects the amino acid sequence, which…. 2) affected the function of the protein, which… 3) is important for the organism. 4) The mutation occurred in a germ cell (except for cancer), which…. 5) participated in fertilization.

21. Mutation: A Random change in the DNA sequence, usually during DNA Replication. Chromosomal In a single gene Point Mutations (Single Nucleotide) Notes

22. Animation of Various Mutations!!! Mutations tutorial

23. Are all mutations Harmful?

24. No! Mutations can be Harmful Silent (with no effect) Of Advantage

28. 1. Which mutation (mistakes) in a gene might have a greater effect on the resulting protein – a missing nucleotide (deletion) or a replaced (substitution) nucleotide? Explain. 2. How might mutations affect the entire organism?

29. Answer: Mistakes in DNA replication have the highest potential to cause damage. a.These errors might cause mistakes in the mRNA and sometimes in the protein. b. Errors in DNA can be inherited, while errors in mRNA or in the protein are not inherited.

30. 1.The DNA is identical in all of your body cells. How come, then, do cells differ from one organ to another? 2. Mutations are said to affect the entire body only if they occur during the making of sperm and egg. Why is that so?

31. Reflect on our unit of DNA and Gene Expression: 1.What did you find most interesting/important? 2. What would you want to know more about?

32. In the Protein Synthesis Lab, Which parts of the process were represented by: 1. The Service Table? 2. The space around the table? 3. The walls of the classroom? 4. The group’s table? 5. The letter on the cards? 6. The instructions on the cards? 7. The final product?