Phenotype: secondary motor neuron anatomical region split, abnormal
Note: This statement combines anatomy and/or ontology terms with phenotype quality terms to create a complete phenotype (EQ) statement. For detailed information on individual terms, click the hyperlinked term name.
Name: secondary motor neuron
Synonyms: secondary motoneuron
Definition: Motor neurons that develop several hours later than primary motoneurons and sprout axons several hours after the primary motor growth cones have extended to the periphery. They have smaller cell bodies and are located more ventrally and laterally in the spinal cord than primary motoneurons. Axons usually project directly out of the spinal cord with no apparent contact with the Mauthner axon and are positioned lateral to the Mauthner axon in their path to the ventral root. Secondary motoneurons have smaller fields, which can overlap one another, and innervate many fewer muscle fibers than primary motoneurons.
Ontology: Anatomy Ontology [ZFA:0009247]
Name: anatomical region
Synonyms:
Definition: A 3D region in space without well-defined compartmental boundaries; for example, the dorsal region of an ectoderm.
Ontology: Spatial Ontology [BSPO:0000070]
Name: split
Synonyms: clefted, divided, forked, septate, subdivided
Definition: A shape quality inhering in a bearer by virtue of the bearer's being divided or broken up into parts or divisions.
Ontology: Phenotypic Quality Ontology [PATO:0001786]