1. Start-Up: If the sequence of nitrogen bases on one strand of DNA is ACTAGGC… what is the sequence of nitrogen bases on the complementary strand?

2. The Flow of Genetic Information in Detail Recall that information in DNA is in the form of specific sequences of nucleotides along the DNA strands G A T C A T C G A This information codes for the creation of proteins when needed When DNA codes for protein synthesis it is called gene expression and it involves two steps: 1. Transcription 2. Translation

4. What is RNA? -RNA is single stranded -has the nitrogen base uracil in place of thymine -and the sugar ribose instead of deoxyribose mRNA – messenger tRNA – transfer

5. Recall that a protein is a long chain of amino acids

7. Translation tRNA carries the amino acid to the ribosome and inserts it at the proper time

9. How mutations alter gene expression Original THE FAT CAT SAW THE DOG Deletion THE FAT CAT SAW THE DOG  THF ATC ATS AWT HED OG Insertion THE FAT CAT SAW THE DOG  THE FTA TCA TSA WTH EDO G