Chapter 9.1 Evolution and its Mechanisms ✓ Flashcards
(12 cards)
What is evolution?
Evolution is the process that results in cumulative, inheritable changes in a population over many generations.
What does the theory of evolution propose?
It proposes that all organisms developed from earlier forms of life and share a common ancestor, originating from a primitive life form.
Why are all organisms fundamentally similar, according to the theory of evolution?
Because they inherited their basic biochemistry from the same initial primitive organism.
Why is evolution still considered a theory?
Although it is supported by strong evidence, it does not fully explain the origin of life from non-living matter, so it remains a scientific theory.
What is the modern synthesis theory of evolution?
It is the current understanding of evolution as changes in allele frequencies within a population’s gene pool over time, combining Darwin’s ideas with genetics.
What does the Hardy-Weinberg Equilibrium Principle state?
It states that allele frequencies in a population will remain constant from generation to generation unless influenced by certain factors.
What are the four mechanisms that can disrupt Hardy-Weinberg equilibrium?
-Mutation
-Natural selection
-Genetic drift
-Migration (gene flow).
What is gene flow?
Gene flow is the transfer of genes from one population to another, often through migration.
What is mutation
A permanent change in the DNA sequence of a gene, which can introduce new alleles into a population.
What is natural selection?
Natural selection is the process where environmental pressures favour certain phenotypes, allowing individuals with advantageous traits to survive and reproduce more successfully than others. This leads to changes in allele frequency and the gene pool over time.
What is genetic drift?
Genetic drift is the change in the allele frequency of a population’s gene pool due to random chance, especially in small populations.
How does natural selection drive evolution?
By increasing the frequency of beneficial alleles in a population, natural selection leads to adaptation and evolutionary change.
