part_of part of part of microsporophyll microsporangium pollen sac A pollen sac is a microsporangium in seed plants. In angiosperms, a single, unfused pollen sac may contain an anther locule or several pollen sacs may fuse so they contain a single anther locule. If you are annotating to this structure for Zea mays or other grasses, please also add an annotation to the corresponding floret type. Choose the most specific term possible from: spikelet floret (PO:0009082), tassel floret (PO:0006310), lower floret of pedicellate spikelet of tassel (PO:0006313), lower floret of sessile spikelet of tassel (PO:0006315), upper floret of pedicellate spikelet of tassel (PO:0006314), upper floret of sessile spikelet of tassel (PO:0006316). PO_GIT:296 plant_anatomy 花粉のう (Japanese, exact) saco pol&#237nico (Spanish, exact) Poaceae microsporangium (narrow) Zea microsporangium (narrow) A microsporangium that is part of a sporophyll and where the pollen grains develop and are located after they develop. rwalls PO:0006444 PO:0006476 PO_GIT:255 2011-02-25T09:17:11Z PO:0025277 anther lobe (narrow)