Q.A lichen represents a symbiotic association between:

A lichen is an obligate symbiotic partnership between an alga (the phycobiont/photobiont, which photosynthesises and supplies nutrition) and a fungus (the mycobiont, which supplies physical protection and anchors the thallus to its substrate via rhizinae). Lichens are classified three separate ways: by habitat (corticolous on bark, lignicolous on wood, saxicolous on rock, terricolous on ground, marine or fresh-water); by thallus form (leprose, crustose - a thin crust; foliose - flat and leaf-like; fruticose - branched and shrub-like); and by how the algal cells are distributed within the thallus - homoiomerous lichens have algal cells scattered evenly throughout the thallus with no distinct layering, while heteromerous lichens have the thallus organised into distinct layers, with the algal cells confined to one separate band within the fungal tissue. A lichen is called an ascolichen if its fungal partner is an Ascomycete, or a basidiolichen if it is a Basidiomycete. Lichens reproduce asexually via fragmentati …