fern sorus cross section. incision through the fern sorus under a microscope with structures: sporangium, indusium, placenta.

anatomy background biological biology botanic botanica botanical botany bracken cell cells closeup cross cut education educational fern ferns forest histological histology incision indusium isolated lab laboratory macro micro micrograph micrography microscope microscopic microscopy nature photo plant school science scientific section slice sliced sores sorus sporangia sporangium spores stained structure structures study university view white