1 Some DMMs can simultaneously measure and display the ac and dc components of a signal. 2  The DMM display can show results three ways (see illustration below): 3  The ac portion of the signal appears in the primary display and the dc portion in the smaller secondary display.
Each lichen specie is one alga species plus one fungus. The alga, a microscopic green plant, makes the food for the duo, while the fungus, a non-green plant, gives the pair support and soaks up moisture.
Symbiosis in lichens is the mutually helpful symbiotic relationship of green algae and/or blue-green algae (cyanobacteria) living among filaments of a fungus. The fungus benefits from the algae or cyanobacteria because they produce food by photosynthesis.urther, the same algal species can occur in association with different fungal partners. Lichens are known in which there is one fungus associated with two or even three algal species. Rarely, the reverse can occur, and two or more fungal species can interact to form the same lichen.