host cell part host apoplast https://github.com/geneontology/go-ontology/issues/20814 https://github.com/geneontology/go-ontology/issues/21343 pg host cell apoplast GO:0140593 2021-02-09T18:56:11Z cellular_component The apoplast region surrounding a host plant cell. Plants may be described as having two major compartments: the living symplast and the non-living apoplast. The apoplast is external to the plasma membrane and includes cell walls, intercellular spaces and the lumen of dead structures such as xylem vessels. Water and solutes pass freely through it. The host is defined as the larger of the organisms involved in a symbiotic interaction.