Chapter 10 & 11: Altering Genetic Material: Mutation, DNA Repair, and Cancer. Flashcards
What is a mutation?
Any change in the nucleotide sequence of DNA.
Mutations may result from?
Errors in DNA replication and physical and chemical agents called MUTAGENS.
Two general categories of mutations within a gene.
- Base Substitution
- Deletion or insertions.
Silent Mutation
Have no affect at all
Missense Mutation
A change in amino acid coding that produces a different amino acid.
Enhances the success of the mutant organism and its descendant.
How does deletion or insertion affect the reading Frame (triplet grouping) or the mRNA?
Lead to significant changes in amino acid sequence downstream of the mutation. Produces a nonfunctional polypeptide.
What are the 4 types of mutations?
- Base Substitution
- Nucleotide Deletion
- Nucleotide Insertion
- Frameshift Mutation
Base Substitution
The replacement of one base by another.
Nucleotide Deletion
The loss of nucleotide
Nucleotide Insertion
The addition of a nucleotide.
Frameshift Mutation
Every codon is changed after the mutation, so a nonfunctional protein will result.
Oncogenes
Genes that cause cancer and are found in viruses.
Proto-Oncogenes
Normal genes with the potential to become oncogenes.
Growth Factors
Hormones (proteins) that stimulate cell division.
Tumor
An overgrowth of cells.
