Objectives
Distinguish between the biotic and abiotic factors in an ecosystem.
Describe how a population differs from a species.
Explain how habitats are impor- tant for organisms.
Key Terms
ecosystem, biotic factor, abiotic factor, organism, species, population, community, habitat
Objectives
Explain the process of evolution by natural selection.
Explain the concept of adaptation.
Describe the steps by which a population of insects becomes resistant to a pesticide.
Key Terms
natural selection, evolution, adaptation, artificial selection, resistance