sentence: Some lichens are symbiotic relationships between fungi and green algae.
sentences_before: The division contains both unicellular and multicellular species. While most species live in freshwater habitats and a large number in marine habitats, other species are adapted to a wide range of environments. Watermelon snow, or 'Chlamydomonas nivalis', lives on summer alpine snowfields. Others live attached to rocks or woody parts of trees.
concept_name: lichen
headings: Chlorophyta
categories: Algae