5. Mutation_Study_Guide.pptx - Unit 5.Mutation Ch-ch-ch-ch-changes Concepts for Study 1 Mutations What are mutations What events cause mutations What is

5. Mutation_Study_Guide.pptx - Unit 5.Mutation...

This preview shows page 1 - 15 out of 119 pages.

Unit 5.Mutation Ch-ch-ch-ch-changes….
Image of page 1

Subscribe to view the full document.

Concepts for Study: 1. Mutations What are mutations? What events cause mutations? What is the relationship between mutations and gene structure? How do transposons create mutations? Mutations and gene function Genes encode proteins by directing assembly of amino acids Mutations alter the gene’s instructions for producing the protein, and consequently the phenotype is altered 2
Image of page 2
Concepts for Study: 2. Mutations are Alleles (“Non-Mendelian” extensions) Single-gene inheritance Pairs of alleles may show deviations from complete dominance and recessiveness (Ex/Incomplete Dominance, Co-Dominance) Different forms of a gene are not limited to two alleles (Ex/Multiple Alleles) One gene may determine more than one trait (Ex/Pleiotropy) Multifactorial inheritance in which the phenotype arises from the interaction of multiple players: the gene and its protein product, the environment, another allele, or other gene products (Ex/Epistasis, Complementary Action, Heterogeneity)
Image of page 3

Subscribe to view the full document.

3. DNA Damage and Repair DNA Damage is caused by a variety of agents and by different mechanisms Replication errors may cause mismatched bases Cells of all types have a number of DNA repair pathways to deal with mismatches and damage Build an understanding of which type of damage is repaired by which pathway 4
Image of page 4
Mutation, Mutation, Mutation 5
Image of page 5

Subscribe to view the full document.

1. Mutations Heritable changes in nucleotide sequences that modify the information content of DNA Remember: Since the DNA is changed, so is the protein product Let’s look at some definitions 6
Image of page 6
Classification of Mutations Deletion –one or more basepairs are lost May result in frameshift mutation (see next slide) Insertion – one or more basepairs are added May result in frameshift mutation (see next slide) Inversion – 180 rotation of piece of DNA, like we talked about when we studied chromosomes Point mutations – nucleotide is replaced by one of the other three nucleotides (e.g. A changed to G). One or a few nucleotides affected 7
Image of page 7

Subscribe to view the full document.

8 Frameshift: insertion or deletion mutation causes a shift in reading frame, which results in reading the codons differently, and the protein product could be changed drastically. Classification of Mutations
Image of page 8
Classification of Mutations Recall: Point mutations – nucleotide is replaced by one of the other three nucleotides (e.g. A changed to G). One or a few nucleotides affected 9
Image of page 9

Subscribe to view the full document.

Types of Point Mutations Missense: mutation causes a change in the mRNA codon that results in a different amino acid being incorporated in the protein Nonsense: mutation causes a change in the mRNA codon to a stop codon Neutral: mutation causes a change in the mRNA codon that results in a new amino acid, but the change does not affect the protein function Silent: mutation causes a change in the mRNA codon that results in a the same amino acid being incorporated in the protein 10
Image of page 10
Image of page 11

Subscribe to view the full document.

Image of page 12
Image of page 13

Subscribe to view the full document.

consequences of a nonsense mutation 14
Image of page 14
Image of page 15

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern

Ask Expert Tutors You can ask 0 bonus questions You can ask 0 questions (0 expire soon) You can ask 0 questions (will expire )
Answers in as fast as 15 minutes