Mutations and Genetic Information
This is a change in the DNA sequence of an organism.
What is a mutation?
This process allows organisms with advantageous traits to survive and reproduce.
What is natural selection?
This mechanism involves random changes in allele frequencies.
What is genetic drift?
These show changes in species over time and transitional forms.
What is the fossil record?
This is the formation of new species.
What is speciation?
This type of mutation replaces one base with another.
What is a substitution?
Natural selection acts on this (physical traits), not directly on genes.
What is phenotype?
This occurs when a small group starts a new population with limited genetic diversity.
What is the founder effect?
Structures that have the same structure but different functions.
What are homologous structures?
This prevents species from mating and producing fertile offspring.
What is reproductive isolation?
These two processes are the main sources of genetic variation in populations.
What are mutations and sexual reproduction?
List the conditions required for natural selection to occur.
What is variation / overpopulation / heritable traits / adaptations?
This occurs when a large portion of a population is randomly eliminated.
What is the bottleneck effect?
These structures are reduced and no longer used.
What are vestigial structures?
Name one type of isolation that can lead to speciation.
What is geographic / behavioral / temporal isolation?
This type of mutation adds or removes bases and can cause a frameshift.
What are insertion or deletion mutations?
This explains why individuals with beneficial traits are more likely to pass them on.
What is an increase in fitness or advantageous traits
This mechanism involves the movement of alleles between populations.
What is gene flow?
Similarity in DNA sequences between species suggests this.
What is common ancestry?
This happens when populations accumulate genetic differences over time.
What is divergence leading to new species?
Explain how mutations can lead to evolution in a population.
What is: mutations create new alleles that, when beneficial, can increase in frequency over generations through natural selection?
Explain why populations—not individuals—evolve.
What is: evolution is a change in allele frequencies in a population over time, not changes within a single organism?
Compare genetic drift and natural selection in how they affect populations.
What is: genetic drift is random and affects allele frequencies by chance, while natural selection is non-random and favors advantageous traits?
Explain how multiple lines of evidence support evolution.
What is: fossil, anatomical, molecular, and embryological evidence all show patterns of change and shared ancestry over time?
Explain how geographic isolation can lead to speciation.
What is: populations separated by a barrier experience different mutations, selection pressures, and drift, eventually becoming reproductively isolated?