(biology) the major taxonomic group of animals and plants; contains classes

the branch of biology that studies plants

eukaryotic one-celled living organisms distinct from multicellular plants and animals: protozoa, slime molds, and eukaryotic algae

used only in former classifications: comprising what is now considered a heterogeneous assemblage of flowerless and seedless organisms: algae; bacteria; fungi; lichens

in former classifications: comprising plants with a vascular system including ferns and fern allies as well as seed plants

a division of nonflowering plants characterized by rhizoids rather than true roots and having little or no organized vascular tissue and showing alternation of generations between gamete-bearing forms and spore-bearing forms; comprises true mosses (Bryopsida) and liverworts (Hepaticopsida) and hornworts (Anthoceropsida)

containing all the vascular plants that do not bear seeds: ferns, horsetails, club mosses, and whisk ferns; in some classifications considered a subdivision of Tracheophyta

the branch of biology that studies plants