12.2 Changes in the gene pool Flashcards
What is the gene pool?
All the alleles that exist within a species.
What does wild-type mean? With mutations?
Wild-type means normal or natural
Mutations means those that are different.
What are somethings that can cause mutations?
- UV light
- Mutagens
- DNA Polymerase can make mistakes during DNA replication
- Transposons can insert themselves, and if they insert themselves into the wrong sequence, it can cause problems.
What is a point mutation?
It’s when one nucleotide in DNA (A,C,T, or G) is swapped for another.
What are the types of point mutations?
Silent Mutation- when the change in the nucleotide has no effect on the final protein synthesized from the gene. Most commonly occurs with changes in in the 3rd codon
Missense Mutation- When the change in the nucleotide results in substituting one amino acid for another in the final protein
Non-Sense Mutation Occur when the change in the nucleotide results in substituting a stop codon for an amino acid in the final protein
What are frameshift mutations?
How can they be subcategorized? (X2)
When nucleotides are inserted into or deleted from the genome.
This causes a change in the ‘reading frame’ of the 3 codon sequence.
Subcategories: insertion or deletion
What are chromosomal mutations?
What are the three types?
Large scale mutations in which segments of DNA are affected.
Deletion Mutation: large segment of DNA is lost, considered frameshift.
Duplication: segment of DNA is copied multiple times in the genome
Inversion: a segment of DNA is reversed within the chromosome.
Insertion Mutation: Occur when a segment of DNA is moved from one chromosome to another (frameshift)
Translocation: segment of DNA from one chromosome is swapped with a segment of DNA from another chromosome.
What is genetic leakage?
It is the flow of genes between species, generally they are closely related.
What is genetic drift?
Changes in the composition of the gene pool due to chance
This is more common is smaller populations.
