QUICK REVIEW DNA is found in the nucleus of the cell

While the copying of DNA is a very accurate process, what happens when a mistake is made?

Mutation A mutation = change in gene sequence. Most mutations are harmful to survival Some mutations are beneficial to survival= adaptation

Harmful Beneficial= adaptation Whether it’s beneficial or not can depend on the environment!

Causes of Mutations Random mistake that isn’t fixed Things in the environment Radiation (ex: nuclear, from the sun) Chemicals

'Severe abnormalities' found in Fukushima butterflies

1 min break

Types of Mutations Substitution: Incorrect pairing of 1 nucleotide base Only changes one codon so only one amino acid protein is changed VC: DNA MutationVC: DNA Mutation (up to :52)

Types of Mutations Deletion/ Addition: an entire base is taken away or added (changes # of rungs) Changes every codon after the mistake so many proteins are changed VC: DNA MutationVC: DNA Mutation (0:53 to end) CONNEX: What type was part 2? Part 3?

How does mutations work? DNA is very accurate when making copies of itself, however, sometimes it makes a mistake. Here’s a DNA sequence AGCCCTTATAGGCTC What are the corresponding base pairs? TCGGGAATATCCGAG Now when it’s being copied it replaces the T with a U. Rewrite the your answer with U’s instead of T’s. UCGGGAAUAUCCGAG What amino acids will this be coded for? Serine, Glycine, Isoleucine, Serine, Glutamic Acid

The Mutation Here’s our original DNA sequence AGCCCTTATAGGCTC Now what are the corresponding base pairs? TTGGGAATATCCGAG (we replaced the C with a T) Now when it’s being copied it replaces the T with a U. Rewrite the your answer with U’s instead of T’s. UUGGGAAUAUCCGAG What amino acids will this be coded for? Leucine, Glycine, Isoleucine, Serine, Glutamic Acid You can see how replacing 1 base will change an amino acid!

What type of mutation was this and why? Substitution b/c incorrect base pair and only 1 codon changed

Original : TAC GGG GGC GTAACCACAACT Here is the other side (copy). 1) Find the error: ATG CGC CCG CATTGGTGTTGA 2) Write the new RNA 3) Form the new codons (you can draw lines on RNA code above to separate) 4) Translate into the new amino acids AUG CGC CCG CATTGGTGTTGA PRACTICE EXAMPLES ON THE HALFSHEET

Original : TAC GGG GGC GTAACCACAACT Here is the other side (copy). 1) Find the error: ATG CGC CCG CATTGGTGTTGA 2) Write the new RNA 3) Form the new codons (you can draw lines on RNA code above to separate) 4) Translate into the new amino acids AUG CGC CCG CATTGGTGTTGA Methionine-Arginine-proline- histadine- tryptophan-cysteine-stop

What’s the difference from the original amino acid? Original: GGG Copy (correct): CCC mRNA: CCC Amino acid: Correct: Methionine- proline -proline Mutation: Methionine-Arginine-proline histadine-tryptophan-cysteine-stop

B: TAA CGG ATG CCA GATCAAATC Here is the other side. Find the error: ATG CCT ACG GT CTAGTTTAG AT_ GCC TAC GGT CTAGTTTAG PRACTICE EXAMPLES ON THE HALFSHEET

TAA CGG ATG CCA AT_ GCC TAC GGTATT What’s the difference from the original amino acid? Original: Copy(correct): mRNA: AUU GCC UAC GGU Amino acid: isoleucine – alanine- tyrosine- glycine methionine-proline –threonine- ??? Correct Mutation

Gone Series by Michael Grant

Pretties Series by Scott Westerfield