Mutations Changes in the DNA sequence Causes of

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Mutations Changes in the DNA sequence

Mutations Changes in the DNA sequence

Causes of mutations Errors when the DNA is copied during replication During protein synthesis-

Causes of mutations Errors when the DNA is copied during replication During protein synthesis- when proteins are constructed When the cell is dividing- Mitosis or meiosis Sometimes external agents, called mutagens, can cause mutations to occur Examples of mutagens include. Radiation, UV sunlight, and certain chemicals like benzene

Mutations in reproductive cells Changes in the DNA of egg and sperm cells If

Mutations in reproductive cells Changes in the DNA of egg and sperm cells If these altered cells become fertilized then the altered genes of the zygote would become part of the genetic makeup of that organism These changes could produce a new trait in the organism It could result in a protein that does not work properly and death of the embryo OR occasionally it may have a positive effect making if faster or stronger or better able to survive

Mutations in body (somatic)cells These types of mutations would not be passed on to

Mutations in body (somatic)cells These types of mutations would not be passed on to the offspring It may cause problems only for the individual. For example it may cause cells to divide uncontrollably resulting in cancer

Types of mutations I. Point mutations II. Frameshift Mutations III. Chromosomal Alterations

Types of mutations I. Point mutations II. Frameshift Mutations III. Chromosomal Alterations

I. Point mutations A change in a single nitrogen base pair in DNA Resulting

I. Point mutations A change in a single nitrogen base pair in DNA Resulting in a change in a single amino acid used in building a protein It can change the functioning of the protein ANALOGY: THE DOG BIT THE CAT DOG BIT THE CAR *Notice that the change in the single letter changed the meaning of the entire sentence.

II. Frameshift Mutations A single nitrogen base is lost or added in a DNA

II. Frameshift Mutations A single nitrogen base is lost or added in a DNA strand Every nitrogen base after the deleted or added base would be out of place ANALOGY: THE DOG BIT THE CAT DOB ITT HEC AT These types of mutations are more harmful because every base after the change is affected.

III. Chromosomal Alterations When big pieces of the chromosomes are altered in some way

III. Chromosomal Alterations When big pieces of the chromosomes are altered in some way These types of mutations are called chromosomal mutations Usually occur during meiosis when egg and sperm are being produced They fall into four categories 1. 2. 3. 4. Deletion Insertion Inversion Translocation

1. DELETIONS Deletions occur when part of a chromosome is left out ABCDEFG ABCD

1. DELETIONS Deletions occur when part of a chromosome is left out ABCDEFG ABCD

2. INSERTIONS (DUPLICATIONS) Insertions (duplications) occur after DNA is replicated when part of one

2. INSERTIONS (DUPLICATIONS) Insertions (duplications) occur after DNA is replicated when part of one chromosome breaks off and rejoins onto another part of the same chromosome so that part of the chromosome is repeated. ABCDEFG ABCDEFDEFG

3. INVERSIONS Inversions occur when part of a chromosome breaks off and rejoins in

3. INVERSIONS Inversions occur when part of a chromosome breaks off and rejoins in reverse order. ABCDEFG ABCFEDG

Inversions

Inversions

Inversions

Inversions

4. Translocations occur when part of a chromosome breaks off and rejoins on another

4. Translocations occur when part of a chromosome breaks off and rejoins on another totally unrelated nonhomologous chromosome. ABCDEFG WXABCDEFG

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Mutations Mutations overview Smallscale mutations Missense mutations NonsenseMutations Mutations overview Smallscale mutations Missense mutations Nonsense
Mutations Mutations Types of Mutations Point Mutations occursMutations Mutations Types of Mutations Point Mutations occurs
GENE Mutations CHROMOSOMAL Mutations DNA Mutations A thirdGENE Mutations CHROMOSOMAL Mutations DNA Mutations A third
DNA MUTATIONS Advanced Biology MUTATIONS Genetic mutations occurDNA MUTATIONS Advanced Biology MUTATIONS Genetic mutations occur
NOTES 13 3 MUTATIONS 1 MUTATIONS MUTATIONS changesNOTES 13 3 MUTATIONS 1 MUTATIONS MUTATIONS changes
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Mutations What are mutations Mutations are changes inMutations What are mutations Mutations are changes in
Mutations Mutations Mutations are changes in the geneticMutations Mutations Mutations are changes in the genetic
Mutations What are Mutations Mutations are changes inMutations What are Mutations Mutations are changes in
Mutations MUTATIONS The sequence of the DNA basesMutations MUTATIONS The sequence of the DNA bases
Mutations Mutations Any change in the DNA sequenceMutations Mutations Any change in the DNA sequence
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Causes of Mutations Activity 2 Causes of MutationsCauses of Mutations Activity 2 Causes of Mutations
MUTATIONS What Are Mutations Changes DNA in theMUTATIONS What Are Mutations Changes DNA in the