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.
Scientists typically classify lichens based on the fungal partner, and the lichen name is the same as the scientific name of the fungal partner. By far the most common fungi found in lichens are sac fungi, or ascomycetes, which produce reproductive spores in special cells shaped like sacs.ichen, living partnership of a fungus and an alga (see Algae). The fungus component is called the mycobiont and is composed of intertwined, threadlike fibers called hyphae that are tightly packed into a tissuelike sheet.