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puberty

(Encyclopedia)puberty pyo͞oˈbərtē [key], period during which the onset of sexual maturity occurs. It usually takes place between the ages of 10 and 15 in both sexes but sometimes occurs as early as 7 or 8 years...

vegetative propagation

(Encyclopedia)vegetative propagation, the ability of plants to reproduce without sexual reproduction, by producing new plants from existing vegetative structures. Some plants, such as the Canada thistle and most ba...

Chlorophyta

(Encyclopedia)Chlorophyta klōrŏfˈətə [key], phylum (division) of the kingdom Protista consisting of the photosynthetic organisms commonly known as green algae. The organisms are largely aquatic or marine. The ...

protozoan

(Encyclopedia)protozoan prōˌtəzōˈən [key], informal term for the unicellular heterotrophs of the kingdom Protista. Protozoans comprise a large, diverse assortment of microscopic or near-microscopic organisms ...

gametophyte

(Encyclopedia)gametophyte gəmēˈtəfītˌ [key], phase of plant life cycles in which the gametes, i.e., egg and sperm, are produced. The gametophyte is haploid, that is, each cell contains a single complete set o...

propagation of plants

(Encyclopedia)propagation of plants is effected in nature chiefly sexually by the seed and the spore, less often by rhizomes and other methods (see reproduction). Vegetative means include cutting, layering, graftin...

tsetse fly

(Encyclopedia)tsetse fly tsĕtˈsē [key], name for any of several bloodsucking African flies of the genus Glossina, and in the same family as the housefly. The larva of the tsetse fly develops inside the body of t...

Asian carp

(Encyclopedia)Asian carp, term for several large, hardy freshwater fish of the family Cyprinidae (the minnow family) that are native to E Asia and have become invasive species in the United States. The fish, which ...

horsetail

(Encyclopedia)horsetail, any plant of the genus Equisetum [Lat.,=horse bristle], the single surviving genus of a large group (Equisetophyta) of primitive vascular plants. Like the ferns and club mosses, relatives o...

spore

(Encyclopedia)spore, term applied both to a resistant or resting stage occurring among various unicellular organisms (especially bacteria) and to an asexual reproductive cell produced by many unicellular plants and...