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Critical Thinking Questions

BiologyCritical Thinking Questions


What are the characteristic features of the chordates?


What can be inferred about the evolution of the cranium and vertebral column from examining hagfishes and lampreys?


Why did gnathostomes replace most agnathans?


Explain why frogs are restricted to a moist environment.


Describe the differences between the larval and adult stages of frogs.


Describe the functions of the three extra-embryonic membranes present in amniotic eggs.


What characteristics differentiate lizards and snakes?


Explain why birds are thought to have evolved from theropod dinosaurs.


Describe three skeletal adaptations that allow for flight in birds.


Describe three unique features of the mammalian skeletal system.


Describe three characteristics of the mammalian brain that differ from other vertebrates.


How did archaic Homo sapiens differ from anatomically modern humans?


Why is it so difficult to determine the sequence of hominin ancestors that have led to modern Homo sapiens?

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