The Embryonic Nervous Systems of Peanut Worms (Sipuncula)and Spoon Worms

question 15

Multiple Choice

The embryonic nervous systems of peanut worms (Sipuncula) and spoon worms (Echiura) show that these worms ________.

• A) are descended from segmented ancestors
• B) have appendages that are homologous with arthropod appendages
• C) do not express Hox genes during development
• D) are similar to each other because of homoplasy
• E) are surprisingly closely related to vertebrates

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Behavioural Theories

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