and Causes What kinds of mutations can occur Mutations Mutations are changes in the genetic material Mutations can produce changes in a single nucleotide to a whole chromosome Gene Mutations ID: 597892
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Slide1
Mutations: Types and CausesSlide2
What kinds of mutations can occur?Slide3
Mutations:
Mutations: are changes in the genetic material.
Mutations can produce changes in a single nucleotide to a whole chromosome. Slide4
Gene Mutations:
Point Mutations: occur at a single point in the DNA Sequence in a gene.
Substitution 2. Insertions 3. DeletionsSlide5
Gene Mutations:
Frameshift
mutations: shift in the reading frame of base pairs caused by an insertion or deletion. Slide6
Chromosomal Mutations:
Chromosomal Mutations: Changes in the number or structure of chromosomes.
4 kinds of chromosomal mutations Slide7
Chromosomal Mutations:
Deletions: Involve the loss of all or part of a chromosome.Slide8
Chromosomal Mutations:
2. Duplications: produce extra copies of parts of a chromosome. Slide9
Chromosomal Mutations:
3. Inversions: reverse the direction of parts of chromosomes.Slide10
Chromosomal Mutations:
4. Translocation: part of one chromosome breaks off and attaches to another Slide11
What are causes
of mutations?Slide12
Mutations:
3
Major Causes
:
1. Errors during Meiosis
2.Errors during DNA replication
3. Environmental exposures Slide13
Cause
1: Meiosis
Meiosis: formation of 4 unique gametes (sex cells)
What happens during Meiosis?
2 Phases: Meiosis I and Meiosis II
Results in 4 haploid cells (cells with half the number of chromosomes carrying unique genetic combinations)
Slide14
Errors During Meiosis:
Errors during
recombination
may occur when chromosomes attempt to swap regions of DNA
Errors during
segregation
may occur when chromosomes segregate into the gametes during meiosis resulting in a gamete containing too many or too few chromosomes Slide15
Cause
2: DNA Replication
DNA Replication: A process by which a
double stranded DNA molecule
is copied to produce
two identical DNA molecules
.
What happens during DNA replication?
Match base pairs with the complementary base. 2. Proofreading to ensure matched correctlySlide16
Errors During DNA Replication:
Error during pairing of base pairs causing too many or too few base pairs to be laid
Errors during pairing of base pairs including mismatching
Proofreading mistakes such as correcting a mismatch causing the wrong base pair to be used and getting rid of the correct base pair Slide17
Cause 3: Environmental Exposures
Environmental Exposure: A specific external agent (mutagen) that may cause the DNA to change.
Examples of Mutagens:
1. Chemical Mutagens: Tobacco, Radium , and Pesticides
2. Physical Mutagens: Radiation, UV light, and gamma rays