Evolutions Test (bio/med) Flashcards
What is variation?
Difference in a physical trait.
What is adaptation?
A feature that allows an organism to better survive in its environment.
What is a population?
A group of organisms of the same species living in the same geographic area who can potentially interbreed and produce fertile offspring.
What is a species?
A group of organisms that can naturally interbreed and produce fertile offspring, forming a distinct, reproductively isolated group.
What is natural selection?
A mechanism of evolution where organisms with traits better suited to their environment tend to survive and reproduce more successfully, passing on those advantageous traits to future generations.
What is artificial selection?
The process where humans intentionally select and breed organisms (plants or animals) with desirable traits to enhance those traits in future generations.
What is evolutionary fitness?
Survival of the Fittest
Organisms best adjusted to their environment are the most successful in surviving and reproducing.
What is descent with modification?
The concept that species evolve over time, passing traits from parent to offspring while undergoing changes.
What does heritable mean?
A trait or characteristic that can be passed down from parents to offspring through genes.
What is a mutation?
A permanent change in the DNA sequence of an organism, virus, or extrachromosomal DNA.
What is phenotype?
The observable characteristics or traits of an organism, resulting from the interaction of its genotype and the environment.
What is genotype?
An organism’s genetic makeup, encompassing all the genes or alleles an individual carries.
What is a gene pool?
The sum of all the genes (including their various alleles) within a population or species at a given time.
How do you find allele frequency?
Count the occurrences of a specific allele in a population and divide that count by the total number of alleles for that gene in the population.
What is genetic drift?
A random fluctuation in the frequency of a gene variant within a population.
What is the bottleneck effect?
A bottleneck event can drastically reduce the number of individuals in a population, leaving behind a small, random sample of the original gene pool.
What is the founder effect?
The loss of genetic variation that occurs when a new population is established by a small group of individuals from a larger, more diverse population.
What is gene flow?
The movement of genetic material (genes or alleles) from one population to another.
What is sexual selection?
Intersexual and Intrasexual
Intrasexual selection is competition between members of the same sex for access to mates, while intersexual selection is where one sex chooses members of the opposite sex.
What is directional selection?
A type of natural selection where one extreme phenotype is favored over others.
What is stabilizing selection?
A type of natural selection that favors intermediate phenotypes within a population.
What is disruptive selection?
A type of natural selection that actively selects against the intermediate in a population, favoring both extremes.
What are the five factors for Hardy-Weinberg equilibrium?
Allele and genotype frequencies remain constant
No mutations, random mating, no natural selection, a large population size, and no gene flow.
What is speciation?
The evolutionary process by which new species arise, typically involving reproductive isolation and genetic divergence.
