7.3.3 Genetic Drift

• What is genetic drift defined as?

  Random changes in allele frequencies
• Smaller populations are more susceptible to genetic drift.


  True
• What is a potential consequence of genetic drift on genetic variation?

  Loss of genetic variation
• What is the effect of natural selection on adaptation?

  Adaptation and evolution
• Contrast genetic drift processes

  1️⃣ Founder Effect: New population established by a small number of individuals

  2️⃣ Population Size: Smaller populations experience more random changes in allele frequencies

  3️⃣ Bottleneck Effect: Sudden reduction in population size due to catastrophic events
• Match the effect with its cause:

  Bottleneck Effect ↔️ Sudden population reduction due to catastrophic events

  Founder Effect ↔️ Establishment of a new population by a small number of individuals
• The bottleneck effect results in a new population with lower genetic variability
• Match the characteristic with the correct type of genetic drift:

  Bottleneck Effect ↔️ Sudden population reduction

  Founder Effect ↔️ Establishment of a new population
• What is the primary cause of genetic drift?

  Random chance events
• What is the founder effect a type of?

  Genetic drift
• What are the consequences of genetic drift on allele frequencies in small populations?

  Loss of rare alleles
• The bottleneck effect can lead to biased allele frequencies in the new population.


  True
• The bottleneck effect can make a population more susceptible to environmental changes.

  True
• Genetic drift reduces genetic diversity in a population.

  True
• Match the characteristic with the evolutionary mechanism:

  Random chance events ↔️ Genetic Drift

  Environmental pressures ↔️ Natural Selection
• How does population size influence genetic drift?

  Smaller populations, greater impact
• Mutation always increases genetic variation within a population.


  True
• Match the evolutionary mechanism with its effect on genetic variation:

  Genetic Drift ↔️ Reduces genetic diversity

  Natural Selection ↔️ Can increase or maintain diversity

  Mutation ↔️ Introduces new alleles

  Gene Flow ↔️ Can increase or decrease diversity
• In natural selection, allele frequencies shift towards advantageous traits
• Genetic drift is a non-random process.

  False
• Genetic drift can reduce genetic variation
• What is the founder effect a type of?

  Genetic drift
• What is the bottleneck effect caused by?

  Sudden reduction in population size
• Genetic drift is directional and driven by environmental pressures.

  False
• Match the mechanism with its effect on genetic diversity:

  Genetic drift ↔️ Reduces genetic variation

  Mutation ↔️ Increases genetic variation

  Gene flow ↔️ Can increase or decrease genetic variation
• Gene flow is directional and aims to equalize allele frequencies
• Genetic drift occurs due to chance events rather than natural selection
• What is the founder effect in genetic drift?

  Genetic drift in newly established populations
• Genetic drift is driven by random chance events, whereas natural selection is driven by environmental pressures
• What is the primary cause of genetic drift?

  Random chance events
• What type of event can cause the bottleneck effect?

  Natural disaster
• Genetic drift is influenced by environmental pressures.

  False
• What can the bottleneck effect make a population more susceptible to?

  Environmental changes
• The bottleneck effect can increase a population's susceptibility to environmental changes.


  True
• Genetic drift refers to the random changes in the allele frequencies
• Genetic drift is dependent on environmental conditions.

  False
• The founder effect can cause the allele frequencies in a new population to differ significantly from the original population.

  True
• What is the primary cause of the bottleneck effect in genetic drift?

  Sudden population reduction
• What is the main cause of the founder effect in genetic drift?

  Establishment by a small group
• How does genetic drift affect allele frequencies in small populations?

  Changes them randomly