Lichens are what type of trophs?

• A. Symbiotic autotrophs
• B. Symbiotic heterotrophs
• C. Parasitic autotrophs
• D. Free-living autotrophs

Answer: (A)

Lichens illustrate a mutualistic partnership where a fungus teams up with a photosynthetic partner such as green algae or cyanobacteria. The photosynthetic partner makes sugars through photosynthesis, supplying carbon compounds to both organisms, while the fungus provides structure, moisture, and protection. Because the lichen’s carbon source comes from photosynthesis within this shared relationship, it functions as an autotroph, classified as a symbiotic autotroph. It’s not best described as a symbiotic heterotroph, parasitic autotroph, or free-living autotroph, since the nutrition hinges on the photosynthetic partner and the organisms rely on each other rather than living independently or exploiting a host.