| 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: | chromosome, telomeric region |
|---|---|
| Synonyms: | nuclear chromosome, telomere, nuclear chromosome, telomeric region, telomere |
| Definition: | The end of a linear chromosome, required for the integrity and maintenance of the end. A chromosome telomere usually includes a region of telomerase-encoded repeats the length of which rarely exceeds 20 bp each and that permits the formation of a telomeric loop (T-loop). The telomeric repeat region is usually preceded by a sub-telomeric region that is gene-poor but rich in repetitive elements. Some telomeres only consist of the latter part (for eg. D. melanogaster telomeres). |
| Ontology: | GO: Cellular Component [GO:0000781] QuickGO AmiGO |