thallophyte(redirected from Lower plant)
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thallophyte,common name for members of the Thallophyta (or Thallobionta), a taxonomic group in some archaic classification systems that comprised algaealgae
[plural of Lat. alga=seaweed], a large and diverse group of primarily aquatic plantlike organisms. These organisms were previously classified as a primitive subkingdom of the plant kingdom, the thallophytes (plants that lack true roots, stems, leaves, and flowers).
..... Click the link for more information. , fungiFungi
, kingdom of heterotrophic single-celled, multinucleated, or multicellular organisms, including yeasts, molds, and mushrooms. The organisms live as parasites, symbionts, or saprobes (see saprophyte).
..... Click the link for more information. , and lichenslichen
, usually slow-growing organism of simple structure, composed of fungi (see Fungi) and photosynthetic green algae or cyanobacteria living together in a symbiotic relationship and resulting in a structure that resembles neither constituent.
..... Click the link for more information. . The thallophytes were considered lower plantsplant,
any organism of the plant kingdom, as opposed to one of the animal kingdom or of the kingdoms Fungi, Protista, or Monera in the five-kingdom system of classification.
..... Click the link for more information. and were grouped together because of they consisted of one cell or a relatively undifferentiated mass of cells called a thallus, instead of having an organized plant body (stem, root, and leaf).
a lower plant (an alga, fungus, or lichen) whose body is not divided into stem and leaves but consists of a thallus. (A plant whose body is divided into stem and leaves is a cormophyte.) Some algae, for example, Caulerpa, Macrocystis, and Sargassum, are externally differentiated into stem and leaf organs, but the anatomic structure of these organs is less complex than in higher plants.