Podcast
Questions and Answers
Which of the following conditions would prevent a population from being in Hardy-Weinberg equilibrium?
Which of the following conditions would prevent a population from being in Hardy-Weinberg equilibrium?
- No natural selection pressures acting on the population.
- Random mating within the population.
- Absence of mutations within the gene pool.
- Presence of gene flow between different populations. (correct)
In a population of birds, a new mutation arises that results in brighter plumage for males. If females preferentially mate with males displaying brighter plumage, what is the most likely effect on the population?
In a population of birds, a new mutation arises that results in brighter plumage for males. If females preferentially mate with males displaying brighter plumage, what is the most likely effect on the population?
- It will lead to a decrease in genetic variation as only the mutated allele is passed on.
- It will disrupt Hardy-Weinberg equilibrium due to non-random mating. (correct)
- It will maintain Hardy-Weinberg equilibrium because the mutation introduces a new trait.
- It will have no effect on the population's genetic structure if the mutation is neutral.
A small group of lizards is separated from the mainland population and colonizes a remote island. Over time, the island lizard population's allele frequencies differ significantly from the mainland population. Which evolutionary mechanism is primarily responsible for this difference?
A small group of lizards is separated from the mainland population and colonizes a remote island. Over time, the island lizard population's allele frequencies differ significantly from the mainland population. Which evolutionary mechanism is primarily responsible for this difference?
- Natural selection, favoring traits that were already common on the mainland.
- Gene flow, as new individuals continue to arrive from the mainland.
- Genetic drift, due to the small initial population size on the island. (correct)
- Mutation, generating entirely new alleles unique to the island population.
A population of butterflies includes individuals with two different wing patterns, determined by a single gene with two alleles. Over several generations, the frequency of one allele increases while the other decreases, eventually disappearing from the population. Which of the following is LEAST likely to cause this change in allele frequency?
A population of butterflies includes individuals with two different wing patterns, determined by a single gene with two alleles. Over several generations, the frequency of one allele increases while the other decreases, eventually disappearing from the population. Which of the following is LEAST likely to cause this change in allele frequency?
A population of fish in a pond is in Hardy-Weinberg equilibrium for a particular gene. A flood connects this pond to a nearby river, introducing a large number of fish with a different allele frequency for that gene. What is the most likely outcome?
A population of fish in a pond is in Hardy-Weinberg equilibrium for a particular gene. A flood connects this pond to a nearby river, introducing a large number of fish with a different allele frequency for that gene. What is the most likely outcome?
In a plant population, a mutation arises that confers resistance to a common fungal disease. Over time, the frequency of the resistance allele increases dramatically. What is the primary mechanism driving this change?
In a plant population, a mutation arises that confers resistance to a common fungal disease. Over time, the frequency of the resistance allele increases dramatically. What is the primary mechanism driving this change?
A population of insects is sprayed with a new pesticide. Initially, most insects are killed, but some survive due to a pre-existing genetic variation. Over time, the population recovers, but the offspring are now highly resistant to the pesticide. Which of the following best explains this scenario?
A population of insects is sprayed with a new pesticide. Initially, most insects are killed, but some survive due to a pre-existing genetic variation. Over time, the population recovers, but the offspring are now highly resistant to the pesticide. Which of the following best explains this scenario?
Which of the following scenarios describes a situation that could lead to a bottleneck effect in a population?
Which of the following scenarios describes a situation that could lead to a bottleneck effect in a population?
Flashcards
Gene Pool
Gene Pool
The total collection of alleles in a population.
Hardy-Weinberg Principle
Hardy-Weinberg Principle
States allele frequencies remain constant without evolutionary influences.
Non-random Mating
Non-random Mating
Mating patterns that affect genotype frequencies but not allele frequencies.
Natural Selection
Natural Selection
Signup and view all the flashcards
Genetic Drift
Genetic Drift
Signup and view all the flashcards
Gene Flow
Gene Flow
Signup and view all the flashcards
Mutation
Mutation
Signup and view all the flashcards
Hardy-Weinberg Equilibrium
Hardy-Weinberg Equilibrium
Signup and view all the flashcards
Study Notes
Mechanisms That Produce Changes in Populations
- A population is a group of organisms of the same species living in the same area at the same time, capable of interbreeding.
- Variations within a population are described by the alleles present in its gene pool.
- Variations in the gene pool affect how organisms present in populations change.
The Hardy-Weinberg Equilibrium
- The Hardy-Weinberg Principle states allele and genotype frequencies in a population remain constant across generations under specific conditions.
- These conditions are: random mating, no natural selection, no genetic drift, no gene flow, and no mutations.
- When these conditions are met, a population is in Hardy-Weinberg equilibrium.
- In Hardy-Weinberg equilibrium, allele frequencies (p and q) and genotype frequencies (p2, 2pq, and q2) remain constant.
- Any deviation from these conditions indicates that evolution is occurring.
Disruptions to Hardy-Weinberg Equilibrium
- Mate Selection: Non-random mating can change genotype frequencies, but not allele frequencies. Organisms might be selective in choosing mates, or only breed with nearby neighbors (or relatives).
- Natural Selection: Individuals with traits better suited to their environment are more likely to survive and reproduce, leading to changes in allele and genotype frequencies over generations.
- Genetic Drift: Random fluctuations in allele frequencies can significantly affect small populations, potentially causing some alleles to be lost or fixed (present in 100% of the population).
- Gene Flow: Immigration and emigration of individuals can introduce or remove alleles from a population, altering allele frequencies.
- Mutations: Mutations create new alleles, which can introduce new genetic variation into a population, altering the existing allele frequencies, though by a small amount.
Significance of Hardy-Weinberg Equilibrium
- Populations can change significantly over time due to changes in alleles and associated genotype frequencies.
- Large-scale changes, potentially leading to new species, occur only after many generations of disruption to equilibrium conditions.
- A population is the smallest unit to evolve.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This lesson explores the mechanisms that drive changes within populations, focusing on the Hardy-Weinberg equilibrium. It explains the conditions necessary for equilibrium and how disruptions to these conditions lead to evolution. Understanding these principles is crucial for studying population genetics.
