AP Biology · Unit 7: Natural Selection
7.11 Variations in Populations
In short
You are expected to understand that the level of variation in a population directly affects its dynamics and resilience. You must know that populations with little genetic diversity are at a higher risk of decline or extinction, whereas genetically diverse populations are more resilient to environmental perturbations because they are more likely to contain individuals capable of withstanding the pressure.
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What else do you need to know about Variations in Populations?
Furthermore, you should recognize that alleles adaptive in one environmental condition may be deleterious in another due to differing selective pressures. The course framework suggests using illustrative examples such as California condors, black-footed ferrets, prairie chickens, potato blight, corn rust, and antibiotic resistance in bacteria to demonstrate these concepts.
Can you do these?
- I can describe how the level of variation in a population affects its ability to respond to environmental changes, and why populations with little diversity are at risk of extinction.
- I can explain why genetically diverse populations are more resilient to environmental perturbations.
- I can explain how an allele that is adaptive in one environment may be deleterious in another due to different selective pressures.
How is Variations in Populations tested on the exam?
This topic is paired with the science practice of Argumentation (Skill 6.C). You may be asked to provide reasoning to justify a claim by connecting evidence to biological theories. In exam questions, this often manifests as evaluating scenarios involving environmental changes and predicting or explaining population survival based on genetic diversity.
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Variations in Populations: common questions
What do you need to know about Variations in Populations for AP Biology?
You are expected to understand that the level of variation in a population directly affects its dynamics and resilience. You must know that populations with little genetic diversity are at a higher risk of decline or extinction, whereas genetically diverse populations are more resilient to environmental perturbations because they are more likely to contain individuals capable of withstanding the pressure.
How is Variations in Populations tested on the AP Biology exam?
This topic is paired with the science practice of Argumentation (Skill 6.C). You may be asked to provide reasoning to justify a claim by connecting evidence to biological theories. In exam questions, this often manifests as evaluating scenarios involving environmental changes and predicting or explaining population survival based on genetic diversity.
How do I know I have mastered Variations in Populations?
Check you can do each of these: describe how the level of variation in a population affects its ability to respond to environmental changes, and why populations with little diversity are at risk of extinction; explain why genetically diverse populations are more resilient to environmental perturbations; explain how an allele that is adaptive in one environment may be deleterious in another due to different selective pressures.
Where does Variations in Populations fit in AP Biology?
Variations in Populations is topic 7.11 in Unit 7: Natural Selection of AP Biology.
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