Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells....
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Transcript of Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells....
![Page 1: Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells. Sometimes, an error occurs when the code is copied. - Such.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649f4e5503460f94c6ffd9/html5/thumbnails/1.jpg)
Chapter 12 Section 4 Mutations
![Page 2: Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells. Sometimes, an error occurs when the code is copied. - Such.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649f4e5503460f94c6ffd9/html5/thumbnails/2.jpg)
Mutations
• DNA contains the code of instructions for cells.
• Sometimes, an error occurs when the code is copied. - Such errors are called mutations.
• Mutations are changes in the genetic material.
![Page 3: Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells. Sometimes, an error occurs when the code is copied. - Such.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649f4e5503460f94c6ffd9/html5/thumbnails/3.jpg)
2 Types of Mutation
• 2 types:
1. Gene mutation produce changes in a single gene
2. Chromosomal mutation produce changes in whole chromosomes
![Page 4: Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells. Sometimes, an error occurs when the code is copied. - Such.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649f4e5503460f94c6ffd9/html5/thumbnails/4.jpg)
Gene Mutations• Point mutation gene mutations involving
changes in 1 or a few nucleotides
- Occurs at a single point in the DNA sequence
• Includes:
a. Substitutions 1 base changed to another
b. Insertions a base is inserted or added
c. Deletions a base is deleted or removed
![Page 5: Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells. Sometimes, an error occurs when the code is copied. - Such.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649f4e5503460f94c6ffd9/html5/thumbnails/5.jpg)
Cont. Gene Mutations
Substitution InsertionDeletion
• Substitutions usually affect no more than a single amino acid
• The effects of insertions/ deletions can be much more dramatic.
![Page 6: Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells. Sometimes, an error occurs when the code is copied. - Such.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649f4e5503460f94c6ffd9/html5/thumbnails/6.jpg)
Cont. Gene Mutations• Frameshift mutations a
change that shifts the “reading frame” of the genetic message (caused insertion/ deletion)
- By shifting the reading frame, frameshift mutations may change every amino acid that follows the point of mutation.
- Can alter a protein so much that it is unable to perform its normal function
![Page 7: Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells. Sometimes, an error occurs when the code is copied. - Such.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649f4e5503460f94c6ffd9/html5/thumbnails/7.jpg)
![Page 8: Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells. Sometimes, an error occurs when the code is copied. - Such.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649f4e5503460f94c6ffd9/html5/thumbnails/8.jpg)
Gene MutationPicture of “Mighty Belgium Blue” cattle
- Alter in myostatin gene
- Produces meatier cattle/ 20% more meat per animal on roughly the same food intake as ordinary animals
![Page 9: Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells. Sometimes, an error occurs when the code is copied. - Such.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649f4e5503460f94c6ffd9/html5/thumbnails/9.jpg)
Chromosomal Mutations• Changes in the number or structure of chromosomes
a. Deletions involves loss of all or part of a chromosome
b. Duplication produce extra copies of parts of a chromosome
c. Inversions reverse the direction of parts of a chromosome
d. Translocation when part of a chromosome breaks off & attaches to another
![Page 10: Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells. Sometimes, an error occurs when the code is copied. - Such.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649f4e5503460f94c6ffd9/html5/thumbnails/10.jpg)
![Page 11: Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells. Sometimes, an error occurs when the code is copied. - Such.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649f4e5503460f94c6ffd9/html5/thumbnails/11.jpg)
Significance of Mutationsa) Harmful mutations
- Produce defective proteins that disrupt normal biological activities- Causes genetic disorders- Associated with many cancers
b) Beneficial mutations- Produce proteins w/ new/ altered activities that can be useful to organisms in different/ changing env- Source of genetic variability in species- Polyploidy an organism w/ extra sets of chromosomes
Ex: polyploid plants are often larger & stronger then diploid plants (bananas & many citrus
fruits)
![Page 12: Chapter 12 Section 4 Mutations. Mutations DNA contains the code of instructions for cells. Sometimes, an error occurs when the code is copied. - Such.](https://reader036.fdocuments.us/reader036/viewer/2022062515/56649f4e5503460f94c6ffd9/html5/thumbnails/12.jpg)
Polyploid