1 / 12

CH. 11.6 Mutations in Genes

CH. 11.6 Mutations in Genes. Objectives: Describe the following types of mutations: Base substitution Base insertion or deletion 2. Explain what can cause a mutation. Vocabulary: Mutation Mutagen. Mutations. Any change in nucleotide sequence of DNA Effects vary: None --> Severe.

trevor
Télécharger la présentation

CH. 11.6 Mutations in Genes

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. CH. 11.6 Mutations in Genes Objectives: • Describe the following types of mutations: • Base substitution • Base insertion or deletion 2. Explain what can cause a mutation. Vocabulary: Mutation Mutagen

  2. Mutations Any change in nucleotide sequence of DNA Effects vary: None --> Severe • http://www.ptbeach.com/167020813143947783/cwp/view.asp?A=3&Q=278050&C=54590 • http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/M/Mutations.html

  3. Base Substitutions Single Base Mutation (Point Mutation) Replacement of one base or nucleotide for another. May or may not cause dysfunction in protein. • http://www.ptbeach.com/167020813143947783/cwp/view.asp?A=3&Q=278050&C=54590 • http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/M/Mutations.html

  4. Base Substitutions • http://www.ptbeach.com/167020813143947783/cwp/view.asp?A=3&Q=278050&C=54590 • http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/M/Mutations.html 1. Silent Mutation: Substitution does not result in a change in amino acid sequence. (More than 1 codon for each amino acid) Ex: GAA --> GAG still makes Glutamine

  5. Base Substitutions 2. Missense Mutation: Substitution DOES result in an amino acid substitution. Can have negative effects. Sickle Cell Anemia

  6. Sickle Cell Anemia • Sickled R.B.C.s are angular and inflexible • Get stuck in blood vessels and block blood flow (=PAIN). • Less functioning RBCs = Fatigue (limits O2 delivered to cells) • http://www.nhlbi.nih.gov/health/health-topics/topics/sca/

  7. Base Substitutions 3. Nonsense Mutation: Substitution results in a STOP CODON. • Shorter, incomplete protein • Negative impacts vary (How much protein was translated?)

  8. Mutations: INSERTIONS & DELETIONS “Frameshift” mutations: Nucleotide is added or removed. • Changes codons, changes amino acid sequence • Bigger impacts/ Different Proteins

  9. Review Mutations

  10. Mutagens: Cause Mutations • Physical Agents High frequency energy • X-rays • UV rays • Chemical Agents • Free-radical oxygens • Certain chemicals (chemotherapy)

  11. Mutations: Source of Genetic Variation Mutations are passed to offspring. Most lead to dysfunctional proteins. Some are lethal. Few - are beneficial (but important to gene pool) Variations in gene pool allow species to survive when environmental conditions change.

More Related