. [ Wikipedia:Iris_muscle ]
术语信息
database
cross reference
- Wikipedia:Iris_muscle
- MA:0001287
- EMAPA:35448
- FMA:49154
- SCTID:280888007
Subsets
uberon_slim
UBPROP 0000008
in aves, stromal mesenchymal cells may migrate to the iris and become skeletal
The muscle cells of the iris are smooth muscle in mammals and amphibians, but are striated muscle in birds and reptiles. Many fish have neither, and, as a result, their irides are unable to dilate and contract, so that the pupil always remains of a fixed size[Romer, via WP]