Copyright Pearson Prentice Hall 12-4 What happens when there is a problem with the DNA sequence? Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Kinds of Mutations Mutations are changes in the genetic material. Many mutations have little or no effect on gene expression. Some mutations are the cause of genetic disorders. Many mutations have a profound effect on the organism. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Kinds of Mutations Kinds of Mutations Mutations that produce changes in a single gene are known as gene mutations. Mutations that produce changes in whole chromosomes are known as chromosomal mutations. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Kinds of Mutations Gene Mutations include: Point mutations a change in one or a few nucleotides which occur at a single point in the DNA sequence. Point mutations include substitutions insertions deletions Copyright Pearson Prentice Hall

Kinds of Mutations/Gene Mutations (3 types) Substitutions usually affect no more than a single amino acid. Gene mutations result from changes in a single gene. In a substitution, one base replaces another. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Kinds of Mutations Insertions & Deletions The effects of insertions and deletions are dramatic. The addition or deletion of a nucleotide causes a shift in the grouping of codons. Changes like these are called frameshift mutations. Frameshift mutations change every amino acid that follows the point of the mutation. Frameshift mutations can alter a protein so much that it is unable to perform its normal functions. Copyright Pearson Prentice Hall

Kinds of Mutations Gene Mutations (3 types) In an insertion, an extra base is inserted into a base sequence. Gene mutations result from changes in a single gene. In an insertion, an extra base is inserted into a base sequence. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Kinds of Mutations In a deletion, the loss of a single base is deleted and the reading frame is shifted. Gene mutations result from changes in a single gene. The loss of a single letter in a sentence models the effects of the deletion of one base in a DNA sequence. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Kinds of Mutations Chromosomal Mutations  Chromosomal mutations involve changes in the number or structure of chromosomes. Chromosomal mutations include deletions duplications inversions translocations. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 12–4 Mutations 12-4 Mutations Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Kinds of Mutations Deletions involve the loss of all or part of a chromosome. Chromosomal mutations involve changes in whole chromosomes. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Kinds of Mutations Duplications produce extra copies of parts of a chromosome. Chromosomal mutations involve changes in whole chromosomes. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Kinds of Mutations Inversions reverse the direction of parts of chromosomes. Chromosomal mutations involve changes in whole chromosomes. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Kinds of Mutations Translocations occurs when part of one chromosome breaks off and attaches to another. Chromosomal mutations involve changes in whole chromosomes. Copyright Pearson Prentice Hall

Significance of Mutations Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 12–4 Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 12–4 A mutation in which all or part of a chromosome is lost is called a(an) duplication. deletion. inversion. point mutation. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 12–4 A mutation that affects every amino acid following an insertion or deletion is called a(an) frameshift mutation. point mutation. chromosomal mutation. inversion. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 12–4 A mutation in which a segment of a chromosome is repeated is called a(an) deletion. inversion. duplication. point mutation. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 12–4 The type of point mutation that usually affects only a single amino acid is called a deletion. a frameshift mutation. an insertion. a substitution. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 12–4 When two different chromosomes exchange some of their material, the mutation is called a(an) inversion. deletion. substitution. translocation. Copyright Pearson Prentice Hall

It’s ragning cats and dogs outnide Substitution of g instead of i in raining Substitution of n instead of s in outside.

It’s raining cats and frogs dogs outside Insertion of the word frogs

It’s raining raining cats and dogs outside Insertion (duplication) of the word raining a second time

It’s raining dogs outside. Deletion of the word cats and the word and.

It’s raining edistuo sgod dna stac. Inversion of the phrase cats and dogs outside.

It’s raining cats anfrogsd dogs outside. Insertion of the word frogs in the middle of the word and.

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