Changes In The Genetic Makeup Of A Population Flashcards
Genetic drift
Changes in Allele frequency due to random change
Gene flow
When individuals with different genes find their way into a population and spread their alleles through reproduction.
Discontinuous variation
Controlled by one gene, either have the trait or you don’t
Continuous variation
Controlled my multiple genes. Can have the trait to different extents
Types of fossil dating
Absolute
Radiometric/isotopic
Carbon
Potassium/argon
Types of mutations
Chromosomal level Point Silent Nonsense Missense
Homologous structures
Has similar physical structure between species but may not have the same function
Analogous structures
Features of an organism that have a similar function but different structure
Vestigial
Features that resemble structures found in other species but are reduced in size and have no apparent function
Types of isolation
Geographical Reproductive Hybrid sterility Mechanical Behavioural
Divergent evolution
Have a common ancestor but because of different selection pressures species have changed over time
Convergent evolution
No common ancestor but due to similar environments/selection pressures they have developed similar features
DNA hybridisation
The higher the number of complementary bases the more tightly the two DNA strands will bind to each other
Mitochondrial DNA
Small and circular therefore survives longer and is better for determining age or relatedness of ancient species
Protein similarities
The more similar the amino acid sequence the more closely related the species
