AP Biology Flashcards: Introduction To Natural Selection

What this deck covers

This deck focuses on Introduction To Natural Selection, giving you a quick way to review the definitions, rules, and examples that matter most for AP Biology.

How to use these flashcards

Work through these flashcards in short sessions. Try to answer each prompt before flipping the card, then revisit any cards you miss until the explanation feels automatic.

Flashcard 1: Identify a factor that can cause genetic drift.

Answer: Random events like natural disasters. Random sampling effects that change allele frequencies regardless of fitness.

Flashcard 2: What is sexual selection?

Answer: Selection based on traits that improve mating success. Favors traits that enhance reproductive success rather than survival.

Flashcard 3: Describe 'stabilizing selection'.

Answer: It favors average phenotypes and reduces variation. Maintains population stability by eliminating extreme variants.

Flashcard 4: Who proposed the theory of natural selection?

Answer: Charles Darwin. English naturalist who formulated the theory in the 19th century.

Flashcard 5: Explain 'disruptive selection'.

Answer: It favors extreme phenotypes over intermediate ones. Promotes genetic diversity by selecting against intermediate forms.

Flashcard 6: Identify the four main principles of natural selection.

Answer: Variation, inheritance, high rate of population growth, differential survival and reproduction. These conditions must exist for natural selection to operate effectively.

Flashcard 7: What does 'differential survival' mean?

Answer: Some organisms are more likely to survive and reproduce than others. Creates unequal reproductive success based on trait advantages.

Flashcard 8: Identify an example of a physiological adaptation.

Answer: Camels storing fat in their humps for energy. Internal body function that enhances survival in harsh desert conditions.

Flashcard 9: Who proposed the theory of natural selection?

Answer: Charles Darwin. English naturalist who formulated the theory in the 19th century.

Flashcard 10: What is meant by 'variation' in a population?

Answer: Differences in physical traits among individuals of a species. Essential for natural selection as it provides diverse traits to select from.

Flashcard 11: What role does 'inheritance' play in natural selection?

Answer: Traits must be heritable for natural selection to act upon them. Only heritable traits can be passed to offspring and accumulate over generations.

Flashcard 12: How does natural selection affect allele frequencies?

Answer: It can increase or decrease allele frequencies based on fitness. Beneficial alleles increase while harmful alleles decrease in frequency.

Flashcard 13: How does the environment influence natural selection?

Answer: It determines which traits are advantageous for survival. Environmental factors create selection pressures that favor certain traits.

Flashcard 14: What is a niche in ecological terms?

Answer: The role and position a species has in its environment. Defines how an organism interacts with its physical and biological environment.

Flashcard 15: What is meant by 'variation' in a population?

Answer: Differences in physical traits among individuals of a species. Essential for natural selection as it provides diverse traits to select from.

Flashcard 16: What results from natural selection over many generations?

Answer: Evolution of species. Gradual change in species characteristics through accumulated adaptations.

Flashcard 17: What is sympatric speciation?

Answer: Speciation that occurs without geographic separation. Reproductive isolation develops within the same geographic area.

Flashcard 18: What is an evolutionary arms race?

Answer: A cycle of adaptations and counter-adaptations between competing species. Continuous reciprocal adaptations between interacting species.

Flashcard 19: What is the bottleneck effect?

Answer: A sharp reduction in population size due to environmental events. Randomly eliminates genetic variants, reducing overall diversity.

Flashcard 20: What is sexual selection?

Answer: Selection based on traits that improve mating success. Favors traits that enhance reproductive success rather than survival.

Flashcard 21: What is natural selection?

Answer: A process where organisms better adapted to their environment tend to survive and reproduce. The driving mechanism of evolution where favorable traits increase survival rates.

Flashcard 22: What results from natural selection over many generations?

Answer: Evolution of species. Gradual change in species characteristics through accumulated adaptations.

Flashcard 23: Identify an example of sexual selection.

Answer: Peacock's tail feathers attracting mates. Ornamental display that signals genetic quality to potential mates.

Flashcard 24: What is an evolutionary arms race?

Answer: A cycle of adaptations and counter-adaptations between competing species. Continuous reciprocal adaptations between interacting species.

Flashcard 25: Identify the four main principles of natural selection.

Answer: Variation, inheritance, high rate of population growth, differential survival and reproduction. These conditions must exist for natural selection to operate effectively.

Flashcard 26: What is gene flow?

Answer: Transfer of genetic variation from one population to another. Migration between populations homogenizes genetic differences.

Flashcard 27: How does mutation contribute to evolution?

Answer: It introduces new genetic variations. Creates novel alleles that provide raw material for selection.

Flashcard 28: Describe 'stabilizing selection'.

Answer: It favors average phenotypes and reduces variation. Maintains population stability by eliminating extreme variants.

Flashcard 29: Describe the founder effect.

Answer: Loss of genetic variation when a new colony is established by a few individuals. Small founding populations carry limited genetic representation.

Flashcard 30: Identify an example of a physiological adaptation.

Answer: Camels storing fat in their humps for energy. Internal body function that enhances survival in harsh desert conditions.

Flashcard 31: How do adaptations arise in a population?

Answer: Through mutations and natural selection over time. Mutations provide variation, selection determines which variants persist.

Flashcard 32: What is a selective advantage?

Answer: A characteristic that improves an organism's chances of survival. Confers higher fitness compared to alternative trait variants.

Flashcard 33: How does artificial selection differ from natural selection?

Answer: Artificial selection is human-directed; natural selection is environment-driven. The agent of selection differs between natural and human-controlled processes.

Flashcard 34: Identify a consequence of reduced genetic diversity.

Answer: Increased vulnerability to diseases. Limited genetic variation reduces adaptive potential and disease resistance.

Flashcard 35: Explain the term 'survival of the fittest'.

Answer: Organisms best adapted to their environment survive and reproduce. Refers to reproductive fitness, not physical strength or dominance.

Flashcard 36: Explain 'disruptive selection'.

Answer: It favors extreme phenotypes over intermediate ones. Promotes genetic diversity by selecting against intermediate forms.

Flashcard 37: What is the significance of genetic variation in a population?

Answer: It provides the raw material for natural selection to act upon. Without variation, all individuals would respond identically to selection pressures.

Flashcard 38: Give an example of a structural adaptation.

Answer: The long neck of a giraffe for reaching high leaves. Physical modification that enhances feeding efficiency and survival.

Flashcard 39: What is directional selection?

Answer: Selection that favors one extreme phenotype over others. Shifts population characteristics toward one end of the trait spectrum.

Flashcard 40: What is speciation?

Answer: The formation of new and distinct species in the course of evolution. Reproductive isolation leads to divergent evolutionary pathways.

Flashcard 41: What is a behavioral adaptation?

Answer: An action or behavior that helps an organism survive in its environment. Learned or instinctive responses that increase survival chances.

Flashcard 42: Identify a factor that can cause genetic drift.

Answer: Random events like natural disasters. Random sampling effects that change allele frequencies regardless of fitness.

Flashcard 43: What is artificial selection?

Answer: Selective breeding by humans to enhance desired traits in organisms. Human intervention replaces natural environmental selection pressures.

Flashcard 44: Identify a consequence of reduced genetic diversity.

Answer: Increased vulnerability to diseases. Limited genetic variation reduces adaptive potential and disease resistance.

Flashcard 45: How does the environment influence natural selection?

Answer: It determines which traits are advantageous for survival. Environmental factors create selection pressures that favor certain traits.

Flashcard 46: How does natural selection affect allele frequencies?

Answer: It can increase or decrease allele frequencies based on fitness. Beneficial alleles increase while harmful alleles decrease in frequency.

Flashcard 47: What is a species?

Answer: A group of organisms that can interbreed and produce fertile offspring. Reproductive compatibility defines the boundaries of species classification.

Flashcard 48: What is speciation?

Answer: The formation of new and distinct species in the course of evolution. Reproductive isolation leads to divergent evolutionary pathways.

Flashcard 49: What is an adaptation?

Answer: A trait that improves an organism's ability to survive and reproduce. Results from natural selection favoring beneficial characteristics.

Flashcard 50: Identify an example of sexual selection.

Answer: Peacock's tail feathers attracting mates. Ornamental display that signals genetic quality to potential mates.

Flashcard 51: What role does 'inheritance' play in natural selection?

Answer: Traits must be heritable for natural selection to act upon them. Only heritable traits can be passed to offspring and accumulate over generations.

Flashcard 52: What is a species?

Answer: A group of organisms that can interbreed and produce fertile offspring. Reproductive compatibility defines the boundaries of species classification.

Flashcard 53: Identify a selection pressure in an environment.

Answer: Predation, competition, climate change. Environmental factors that influence which traits are advantageous.

Flashcard 54: Identify a selection pressure in an environment.

Answer: Predation, competition, climate change. Environmental factors that influence which traits are advantageous.

Flashcard 55: How does artificial selection differ from natural selection?

Answer: Artificial selection is human-directed; natural selection is environment-driven. The agent of selection differs between natural and human-controlled processes.

Flashcard 56: Define 'fitness' in an evolutionary context.

Answer: The ability of an organism to survive and reproduce in its environment. Measured by reproductive success and adaptation to environmental pressures.

Flashcard 57: What is a behavioral adaptation?

Answer: An action or behavior that helps an organism survive in its environment. Learned or instinctive responses that increase survival chances.

Flashcard 58: What is a selective advantage?

Answer: A characteristic that improves an organism's chances of survival. Confers higher fitness compared to alternative trait variants.

Flashcard 59: What is a niche in ecological terms?

Answer: The role and position a species has in its environment. Defines how an organism interacts with its physical and biological environment.

Flashcard 60: Describe allopatric speciation.

Answer: Speciation that occurs due to geographic isolation. Physical barriers prevent gene flow between diverging populations.

Flashcard 61: Why is overproduction of offspring important for natural selection?

Answer: It leads to competition, ensuring only the fittest survive. Creates resource scarcity that intensifies selection pressure.

Flashcard 62: How does mutation contribute to evolution?

Answer: It introduces new genetic variations. Creates novel alleles that provide raw material for selection.

Flashcard 63: Explain the term 'survival of the fittest'.

Answer: Organisms best adapted to their environment survive and reproduce. Refers to reproductive fitness, not physical strength or dominance.

Flashcard 64: How do adaptations arise in a population?

Answer: Through mutations and natural selection over time. Mutations provide variation, selection determines which variants persist.

Flashcard 65: Why is overproduction of offspring important for natural selection?

Answer: It leads to competition, ensuring only the fittest survive. Creates resource scarcity that intensifies selection pressure.

Flashcard 66: Describe allopatric speciation.

Answer: Speciation that occurs due to geographic isolation. Physical barriers prevent gene flow between diverging populations.

Flashcard 67: Give an example of a structural adaptation.

Answer: The long neck of a giraffe for reaching high leaves. Physical modification that enhances feeding efficiency and survival.

Flashcard 68: Describe the founder effect.

Answer: Loss of genetic variation when a new colony is established by a few individuals. Small founding populations carry limited genetic representation.

Flashcard 69: Define 'fitness' in an evolutionary context.

Answer: The ability of an organism to survive and reproduce in its environment. Measured by reproductive success and adaptation to environmental pressures.

Flashcard 70: What does 'differential survival' mean?

Answer: Some organisms are more likely to survive and reproduce than others. Creates unequal reproductive success based on trait advantages.

Flashcard 71: What is natural selection?

Answer: A process where organisms better adapted to their environment tend to survive and reproduce. The driving mechanism of evolution where favorable traits increase survival rates.

Flashcard 72: What is the significance of genetic variation in a population?

Answer: It provides the raw material for natural selection to act upon. Without variation, all individuals would respond identically to selection pressures.