There exists a close association between the alga and the fungus within a lichen. The fungus:
There exists a close association between the alga and the fungus within a lichen. The fungus:
provides protection, anchorage and absorption for the algae
provides food for the alga
fixes the atmospheric nitrogen for the alga
releases oxygen for the alga.
Solution
Lichens are unique, double organisms that consist of two unrelated components, an alga and/ or cyanobacterium (photobiont) and a fungus (mycobiont). Lichens are unique, double organisms that consist of two unrelated components, an alga and/or cyanobacterium (photobiont) and a fungus (mycobiont)
Related Theory
Lichens have a body called a thallus, an outer, tightly packed fungal layer called a cortex, and an inner, loosely packed fungal layer called a medulla. Lichens use hyphal bundles called rhizines to attach to the substrate.