SFSU exam 1 bio 240 questions and verified
answers (detailed & elaborated) ACTUAL EXAM 2025
TESTS!!
Allele
Ans: - Different versions of a gene that contribute to genetic diversity.
Quiz Mutation
Ans: - A change in the DNA sequence that occurred without purpose or intent, which can lead to
variation in traits. 1 mechanism of evolutionary change.
Quiz Genetic drift
Ans: -Random changes in allele frequencies in a population, often affectingsmall populations. 1
mechanism of evolutionary change.
Quiz Bottleneck Effect
Ans: A sharp reduction in the size of a population due to environmental events, leading to a loss of
genetic diversity
Quiz Founder effect
,Ans: Genetic drift that occurs when a new population is established by a very small number of
individuals
Quiz Gene flow
Ans: - The transfer of genetic material between populations, increasing or maintaining genetic diversity.
Quiz Natural selection
Ans: Change in allele frequencies in populations over time DUE to differential survival and reproduction.
Under selection, traits (and the genotypes underneath them, alleles) will increase or decrease in a
population over time depending on how they affect fitness. 1 mechanism of evolutionary change
Quiz Fitness
Ans: Long term reproductive success
Quiz Directional selection
Ans: a type of selection where one extreme phenotype is favored over others
Quiz Stabilizing selection
Ans: a type of selection where the intermediate phenotypes are favored over extremes
, Quiz Disruptive selection
Ans: a type of selection where both extreme phenotypes are favored over intermediate ones.
Quiz phenotypic plasticity
Ans: the ability of one genotype to produce different phenotypes in response to environmental
changes. NOT evolution or selection.
Quiz speciation
Ans: the formation of new and distinct species in the course of evolution.
Quiz allopatric speciation
Ans: speciation the occurs when populations are geographically separated
Quiz sympatric speciation
Ans: speciation that occurs WITHOUT geographic separation often through ecological or behavioral
differences.
Quiz PREzygotic barrier
Ans: reproductive barriers that occur after feralization leading to unviable or sterile offspring
answers (detailed & elaborated) ACTUAL EXAM 2025
TESTS!!
Allele
Ans: - Different versions of a gene that contribute to genetic diversity.
Quiz Mutation
Ans: - A change in the DNA sequence that occurred without purpose or intent, which can lead to
variation in traits. 1 mechanism of evolutionary change.
Quiz Genetic drift
Ans: -Random changes in allele frequencies in a population, often affectingsmall populations. 1
mechanism of evolutionary change.
Quiz Bottleneck Effect
Ans: A sharp reduction in the size of a population due to environmental events, leading to a loss of
genetic diversity
Quiz Founder effect
,Ans: Genetic drift that occurs when a new population is established by a very small number of
individuals
Quiz Gene flow
Ans: - The transfer of genetic material between populations, increasing or maintaining genetic diversity.
Quiz Natural selection
Ans: Change in allele frequencies in populations over time DUE to differential survival and reproduction.
Under selection, traits (and the genotypes underneath them, alleles) will increase or decrease in a
population over time depending on how they affect fitness. 1 mechanism of evolutionary change
Quiz Fitness
Ans: Long term reproductive success
Quiz Directional selection
Ans: a type of selection where one extreme phenotype is favored over others
Quiz Stabilizing selection
Ans: a type of selection where the intermediate phenotypes are favored over extremes
, Quiz Disruptive selection
Ans: a type of selection where both extreme phenotypes are favored over intermediate ones.
Quiz phenotypic plasticity
Ans: the ability of one genotype to produce different phenotypes in response to environmental
changes. NOT evolution or selection.
Quiz speciation
Ans: the formation of new and distinct species in the course of evolution.
Quiz allopatric speciation
Ans: speciation the occurs when populations are geographically separated
Quiz sympatric speciation
Ans: speciation that occurs WITHOUT geographic separation often through ecological or behavioral
differences.
Quiz PREzygotic barrier
Ans: reproductive barriers that occur after feralization leading to unviable or sterile offspring
