Lecture 4 Flashcards
Genotype
Genetic constitution of an organism
Phenotype
An observable feature: physiological, anatomical, even biocheical
Genome
Entirety of an organism’s DNA
3 Sources of Genetic Variation
Mutation, independent assortment, recombination
Mutation Definition
Stable change in DNA sequence
Mutation occurs at a x rate
Low
Types of effects mutation has on fitness
Neutral, e.g. at a non coding region, deleterious, beneficial
Characteristics of Mutation
- Inevitable: every single biological organism on earth has
- Random with respect to fitness
- Rate depends on type. gene and environment
4 Types of Mutations
Point mutations, insertions/deletions, changes in re[eat number and chromosomal rearrangements (inversions)
Mutation: Point Mutation
Single change in purine/pyrimidine base, a base substituted for another
Mutation: Insertions/Deletions
(Indels) change in length: one more/less base added/removed
Mutation: Change in Repeat Number
A motif repeated over and over again: loses track in the number of times repeated
Mutation: Chromosomal Rearrangements
Double strand break: doesn’t know which end is which, the strand is inverted
Silent Mutation and Amino Acids
If a mutation occurs on a non coding gene, or if the mutation codes for the same nucleotide, the mutation is silent
Independent Assortment
Allows different combinations of parental chromosomes to create a larger amount of possible progeny chromosomes
