The Amphibians' Unique Contribution to the Evolution of Land Vertebrates

question 55

Multiple Choice

The amphibians' unique contribution to the evolution of land vertebrates was

• A)respiration by gills.
• B)respiration through the skin.
• C)separation of lung/gill and systemic (body)circulation.
• D)development of the tail for propulsion.
• E)the leathery waterproof egg shell.

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