| 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: | sarcomere organization | 
|---|---|
| Synonyms: | sarcomere alignment, sarcomere organisation | 
| Definition: | The myofibril assembly process that results in the organization of muscle actomyosin into sarcomeres. The sarcomere is the repeating unit of a myofibril in a muscle cell, composed of an array of overlapping thick and thin filaments between two adjacent Z discs. | 
| Ontology: | GO: Biological Process [GO:0045214] QuickGO AmiGO |