| Name: | atrium | 
|---|---|
| Synonyms: | |
| Definition: | Cavitated compound organ that receives inflow of deoxygenated blood and delivers it to a muscular cardiac ventricle. Valves are present to direct flow. There are only two chambers present in the fish heart. | 
| Ontology: | Anatomy Ontology [ZFA:0000471] | 
| Name: | dorsal region | 
|---|---|
| Synonyms: | |
| Definition: | Anatomical region dorsally located on the body or body part. | 
| Ontology: | Spatial Ontology [BSPO:0000079] |