IB Biology Exam Prep

Correct Response: A. Lichens are a mutually beneficial association between fungi and photobionts (either algae or cyanobacteria). The photobiont provides carbon for the lichen through photosynthesis. In the case of cyanobacteria. Absorption of decomposing organic material (B), the accumulation of wind-borne particulate matter (C), and the assimilation of solutes dissolved in precipitation (D) are not significant means by which lichens obtain carbon.