5. Is the tubular-dorsal nervous system of chordates associated to radial or lateral symmetry? How does that explain the complexity level of the nervous system reached by the vertebrate evolutionary branch?
Gap-fill exercise
Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!