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.
li chen 1 any complex organism of the group lichenes composed of a fungus in symbiotic union with an alga most commonly forming crusty patches on rocks and trees 2 any of various eruptive skin diseases3 to cover with or as if with lichens lÄ«chÄn leichá¸ni chen 1 any complex organism of the group lichenes composed of a fungus in symbiotic union with an alga most commonly forming crusty patches on rocks and trees 2 any of various eruptive skin diseases 3 to cover with or as if with lichens lÄ«chÄn leichá¸n li chen ous adj