to learn whether presence of a specific neuron , the mauthner ( m ) cell , is required for the organization , during embryogenesis , of an associated synaptic neuropil , the m-axon cap , m-cell precursors were experimentally deleted in embryos of the zebra fish ( brachydanio rerio ) and the axolotl ( ambystoma mexicanum ) .
C0027882
neuron
C0004461
axon