  Understand what mutations are  Understand how they occur  Analyze the different types of mutations  Understand how mutations affect amino acid sequences and proteins Objective

  Central Dogma  DNA is transcribed into RNA, RNA is translated into proteins  3 nitrogenous bases give us a codon  One codon codes for a specific amino acid  ie. AUG codes for “start” and Methionine  Peptide bonds hold amino acids together  Amino acids give us proteins! What we know so far!

  If the DNA in the cells inside your entire body were lined up end to end, they would stretch around the Earth and Jupiter 60 times in distance!  Many mechanisms were developed to protect DNA from change within the cell but mutations still happens  Any change in the DNA sequence is called a mutation! What is a mutation?

  Mutations can affect the reproductive cells of an organism.  Changes the sequence of the nucleotides within a gene (sperm or egg cell)  If this cell takes part in fertilization, the altered gene becomes part of the genetic make-up.  Can result in a new trait or a protein that doesn’t work correctly.  May (few times) have a positive effect  Mutation may make organism faster, stronger, and better to survive in environment.  Basis of evolutionary theory

  Powerful radiation could cause DNA in a non- reproductive cell to change.  This mutation would not be passed on, but could cause problems for the individual.  Impaired function of the cell  ie. Stomach acid, skin cells  When a cell divides, the mutation will carry on. Mutations in Body Cells

  Some mutations can affect the genes that control cell division!  Rapid division and growth (result)  This mutation is known better as cancer. (uncontrolled division of cells)  ie. UV radiation in sunlight can change the DNA in skin cells ; cells produce rapidly, causing skin cancer. Cancer is a mutation!

  Point Mutation  A change in a single base pair in DNA. Types of Mutations The first point mutation did not result in a change in the protein. The second point mutation caused a change in the protein. This was a stop codon The third point mutation coded for a different protein as well. THE DOG BIT THE CA T THE DOG BIT THE CA R..the meaning of the sentence changed due to that one change in a word…point mutations!

  Frameshift Mutation  When a single base is added or deleted from DNA Types of Mutations THE DO G BIT THE CAT THE DOB ITT HEC AT The G was deleted from the sentence resulting in a scrambled sentence; frameshift mutation. THE DOG BIT THE CAT THE DOG B B I TTH ECA T The B was added to the sentence resulting in a scrambled sentence; frameshift mutation.

 Changes sequence in nitrogenous bases May cause change in amino acid sequence Different amino acids sequence may code for different proteins that intended. Function of cell may be altered Phenotype (physical appearance) of trait may be altered. Why mutations Matter!

  Chemicals  Asbestos was used to insulate buildings  Known to cause lung cancer an disease  UV Rays Cause of Mutations

  What is a mutation?  What different types of mutations are there?  Can you describe them?  Why do mutations matter? Knowledge Check