1 / 11

What ’ s the Purpose of All This DNA Stuff?

What ’ s the Purpose of All This DNA Stuff?. *Sequence of nitrogen bases along the DNA strand (genes) code for an amino acid sequence (which make up proteins) - Proteins are responsible for the traits organisms possess. Mutations. A change in the genetic information. Kinds of Mutations.

maxima
Download Presentation

What ’ s the Purpose of All This DNA Stuff?

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. What’s the Purpose of All This DNA Stuff? *Sequence of nitrogen bases along the DNA strand (genes) code for an amino acid sequence (which make up proteins) - Proteins are responsible for the traits organisms possess.

  2. Mutations • A change in the genetic information

  3. Kinds of Mutations Point mutation: gene mutation involving a change in 1 or a few nucleotides Substitutions = 1 base is changed for another Ex: G toC or A to G insertions = 1 base is inserted in the sequence CGTACT - CGTAACT

  4. deletion = 1 base is deleted from the sequence • CGTACT - CTACT • Substitutions will usually only affect 1 amino acid • Insertions or deletions will change the reading frame of mRNA (how we decipher the mRNA into AA’s)

  5. Frameshift mutation: mutations that shift the reading frame of the genetic message - Will change the amino acid sequence of every AA that follows the mutation = protein probably won’t function correctly Insertion and deletion

  6. Significance of Mutations • Some mutations do not have any affect (silent mutation) • some change function of proteins produced; changing biological activities of an organism • some are beneficial and help an organism survive in a changing environment

  7. Mutations in body cells won’t be passed on to offspring • mutations in gametes will Polyploidy: condition in which an organism has extra sets of chromosomes - Can make some organisms stronger & larger

  8. Chromosomal Mutations 4 Types: • Deletion = loss of part or all of a chromosome • Duplication = produce extra copies of parts of a chromosome • Inversion = reverse the direction of parts of a chromosome

  9. 4. Translocation = part of a chromosome breaks off and reattaches to another

  10. Assignment: Work together with a partner (or by yourself) and analyze the DNA strands on the handout. You will decided what kind of mutation has occurred.

More Related