NY Regents Living Environment — free MCQ practice

1. Genetic diversity in a population comes from two main mechanisms. 2. The first is mutation, a change in DNA that is the ultimate source of new alleles. 3. The second is sexual reproduction, which assembles unique combinations of alleles in each offspring. 4. Geographic isolation and gene flow are discussed elsewhere as factors in speciation, not as the two main sources of genetic diversity within a population. 5. Natural selection acts on existing variation rather than generating new genetic variation itself, so it does not belong in this pair. _Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 18 "Evolution and the Origin of Species", section Processes and Patterns of Evolution_

1. A heritable trait that helps survival and reproduction in the present environment is called an adaptation. 2. The webbed feet of platypuses and the snow leopard's thick fur are both examples of adaptations to a specific environment. 3. A mutation is a change in DNA that may or may not become an adaptation, so the two terms are not interchangeable. 4. Vestigial and homologous structures are separate evidence categories for evolution, not the general term for a helpful heritable trait. _Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 18 "Evolution and the Origin of Species", section Processes and Patterns of Evolution_

1. Divergence can occur even without physical barriers separating individuals in the same habitat. 2. The process of speciation within the same space is called sympatric speciation. 3. The prefix sym means same, so sympatric means same homeland, in contrast to allopatric meaning other homeland. 4. Adaptive radiation and punctuated equilibrium describe different patterns, and allopatric speciation is the opposite process, requiring geographic separation. _Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 18 "Evolution and the Origin of Species", section Sympatric Speciation_