| Name: | testis |
|---|---|
| Synonyms: | testes |
| Definition: | Male reproductive organ. Adult zebrafish testes are paired organs forming elongated structures, internally organized into tubules. These tubules are formed by seminiferous epithelium containing cysts of spermatogonia and spermatocytes surrounded by somatic support cells, called Sertoli cells. Cysts are arranged around a lumen containing spermatozoa that is connected to the efferent ducts. The interstitial regions between the tubules contain the steroid-producing Leydig cells, connective tissue, and blood vessels. |
| Ontology: | Anatomy Ontology [ZFA:0000598] |
| Name: | nucleus |
|---|---|
| Synonyms: | cell nucleus, horsetail nucleus |
| Definition: | A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent. |
| Ontology: | GO: Cellular Component [GO:0005634] QuickGO AmiGO |