Term: branchiostegal ray osteoblast
Note: This page represents a term created by the combination ("post-composition") of two ontology terms. For more information on the individual terms, click the hyperlinked name.
Name: branchiostegal ray
Synonyms: branchiostegal rays
Definition: Dermal bone that is a bilaterally paired and flattened element that supports the branchiostegal membrane. Three dermal branchiostegal rays form in the branchiostegal membrane ventral to the ceratohyal cartilage. The most posterior ray, branchiostegal 3, ossifies first (3.4 mm NL), and the most anterior ray, branchiostegal 1, ossifies last (5.5 mm NL). The most posterior two branchiostegals (2 and 3) insert externally on the ceratohyal; their anterodorsal tips are thickened triangles, and the rays are expanded. The bifurcated tip of the acinaciform anteriormost ray lies at the ventral margin of the ceratohyal.
Ontology: Anatomy Ontology [ZFA:0000476]
Name: osteoblast
Synonyms: osteoblasts
Definition: A bone-forming cell which secretes an extracellular matrix. Hydroxyapatite crystals are then deposited into the matrix to form bone.
Ontology: Anatomy Ontology [ZFA:0009031]