| 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: | lower region |
|---|---|
| Synonyms: | |
| Definition: | |
| Ontology: | Spatial Ontology [BSPO:0000032] |