GENETICS AND EVOLUTION
EVOLUTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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They are unrelated.
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They are the same organism.
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They share a common ancestor.
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They evolved in a similar environment.
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Detailed explanation-1: -Two organisms have homologous structures. Which can most likely be concluded about the two organisms? They are unrelated.
Detailed explanation-2: -Evidence for evolution is provided by homologous structures. These are structures shared by related organisms that were inherited from a common ancestor. Other evidence for evolution is provided by analogous structures. These are structures that unrelated organisms share because they evolved to do the same job.
Detailed explanation-3: -Homologous structures If two or more species share a unique physical trait they may all have inherited this trait from a common ancestor. Traits that are shared due to common ancestry are homologous structures. The similar bone arrangement of the human, bird, and whale forelimb is a structural homology.
Detailed explanation-4: -An example of homologous structures are the limbs of humans, cats, whales, and bats. Regardless of whether it is an arm, leg, flipper or wing, these structures are built upon the same bone structure. Homologies are the result of divergent evolution.
Detailed explanation-5: -Ancestral organism shared by two or more descendent lineages-in other words, an ancestor that they have in common. For example, the common ancestors of two biological siblings include their parents and grandparents; the common ancestors of a coyote and a wolf include the first canine and the first mammal.