2. Study the diagram below and be prepared to answer the following questions: What processes are represented by the 1, 2 and 3 in the diagram? What processes are represented by the 1, 2 and 3 in the diagram? What is another name for a polypeptide? What is another name for a polypeptide?

3. Get a copy of the Stemscopedia from the cabinet and create a tree map like the one below in your notebook..

5. Mutations Gene Mutations Chromosomal Mutations substitution deletioninsertion duplication inversion deletion translocation

6. mutation. Yes, it does. When this happens, we call it a mutation. Does the DNA sequence ever get messed up?

8. A mutation is a change in the nucleotide sequence of DNA. And as you can probably guess, a change in DNA leads to a change in mRNA, which can lead to a change in protein synthesis.

10. We can think about the DNA sequence of a gene as a sentence made up entirely of three-letter words. In the sequence, each three-letter word is a Codon, specifying a single amino acid in a Protein. Thesunwashotbuttheoldmandidnotgethissunhat

11. The sun was hot but the old man did not get his sun hat This sentence represents a gene. Each letter corresponds to a nucleotide base, and each word represents a codon.

12. Thesunwashotbuttheoldmandidnotgethissunhat T hes unw ash otb utt heo ldm and idn otg eth iss unh at

13. Aren’t There Any Good Mutations? Yes, there are! On rare occasions, a mutation can make an organism more likely to survive and reproduce.

14. For example, a species of plant might produce a chemical with a scent that attracts pollinating flies. A mutation in one of the plants could make it produce a slightly different scent—one that is even more attractive to pollinators. This type of mutation would be beneficial to the plant.

16. How bad can one change really be? How many amino acids would be effected if the mutation below occurred? CUUGAUACA  CUUGAAACA

17. How bad can one change really be? But what if... But what if... AUGCGUCCC  UGACGUCCC

18. However, most mutations don’t have an effect on an organism. How can that happen? For one thing, not all mutations lead to a different protein being made. There are more codons than there are amino acids.

19. So, more than one codon can code for the same amino acid. What would happen if the mRNA codon CUC were mutated to CUG? CGU were mutated to CGA? ACG were mutated to ACC?