Types of mutations
This presentation is the property of its rightful owner.
Sponsored Links
1 / 8

Types of mutations PowerPoint PPT Presentation


  • 94 Views
  • Uploaded on
  • Presentation posted in: General

Types of mutations . Mutations are changes in the genetic material There are two basic types of mutations: Gene mutations - mutations that produce changes in a single gene Chromosomal mutations - mutations that produce changes in whole chromosomes. Gene mutations . Point mutations:

Download Presentation

Types of mutations

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.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Types of mutations

Types of mutations

  • Mutations are changes in the genetic material

  • There are two basic types of mutations:

    • Gene mutations - mutations that produce changes in a single gene

    • Chromosomal mutations - mutations that produce changes in whole chromosomes


Gene mutations

Gene mutations

  • Point mutations:

    • Involves changes in one or a few nucleotides (they occur at a single point in the DNA sequence)

    • They can be:

      • Substitutions

      • Insertions

      • Deletions


Substitutions

Substitutions

  • One base is changed to another

  • Substitutions usually only affect a single amino acid


Insertions and deletions

Insertions and Deletions

  • A base is either inserted or removed from the DNA sequence

  • If a nucleotide is added or deleted, the bases are still read in groups of three, so every codon after is changed

  • These types of mutations cause Frameshift mutations

  • Can cause major changes to the protein, to the point where it can’t perform its normal function


Chromosomal mutations

Chromosomal mutations

  • Involve the chromosomal changes in the number or structure of chromosomes

  • Can change the locations of genes on chromosomes, and the number of copies of some genes

  • Four types:

    • Deletions

    • Duplications

    • Inversions

    • Translocations


Duplications and deletion

Duplications and Deletion

  • Duplication (Nondisjunction):

    • The failure of a chromosome to separate from its homologue during meiosis

    • One gamete receives an extra copy of a chromosome and the other lacks it

  • Deletion:

    • Loss of a piece of a chromosome


Translocations and inversions

Translocations and Inversions

  • Translocation:

    • When a chromosome piece breaks off and reattaches to another, nonhomologous chromosome

  • Inversion:

    • Chromosome segment breaks off and then reattaches in reverse orientation to the same chromosome


Significance of mutations

Significance of Mutations

  • Most mutations are neutral (they have little or no effect)

  • Mutations that cause dramatic changes in protein structure or gene activity can be very harmful

  • Mutations are a source of genetic variability in a species

  • Polyploidy- a mutation where an organism has an extra set of chromosomes

    • Polyploid plants are often larger and stronger


  • Login