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clone

(Encyclopedia)clone, group of organisms, all of which are descended from a single individual through asexual reproduction, as in a pure cell culture of bacteria. Except for changes in the hereditary material that c...

Phaeophyta

(Encyclopedia)Phaeophyta fēŏfˈətə [key], phylum (division) of the kingdom Protista consisting of those organisms commonly called brown algae. Many of the world's familiar seaweeds are members of Phaeophyta. Th...

impotence

(Encyclopedia)impotence imˈpətəns [key], inhibited sexual excitement in a man during sexual activity that, despite an unaffected desire for sex, results in inability to attain or maintain a penile erection. Know...

pollen

(Encyclopedia)pollen, minute grains, usually yellow in color but occasionally white, brown, red, or purple, borne in the anther sac at the tip of the slender filament of the stamen of a flowering plant or in the ma...

silkworm

(Encyclopedia)silkworm, name for the larva of various species of moths, indigenous to Asia and Africa but now domesticated and raised for silk production throughout most of the temperate zone. The culture of silkwo...

slime mold

(Encyclopedia)slime mold or slime fungus, a heterotrophic organism once regarded as a fungus but later classified with the Protista. In a recent system of classification based on analysis of nucleic acid (genetic m...

Brachiopoda

(Encyclopedia)CE5 Internal anatomy of a lamp shell, Magellania, representative of the phylum Brachiopoda Brachiopoda brākēŏpˈədə [key], phylum of shelled sessile or sedentary marine animals, commonly know...

printing

(Encyclopedia)printing, means of producing reproductions of written material or images in multiple copies. There are four traditional types of printing: relief printing (with which this article is mainly concerned)...

Rhodophyta

(Encyclopedia)Rhodophyta rōdŏfˈətə [key], phylum (division) of the kingdom Protista consisting of the photosynthetic organisms commonly known as red algae. Most of the world's seaweeds belong to this group. Me...

insecticides

(Encyclopedia)insecticides, chemical, biological, or other agents used to destroy insect pests; the term commonly refers to chemical agents only. The liabilities of chemical insecticides have encouraged interest ...