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Monera

(Encyclopedia)Monera, taxonomic kingdom that comprises the prokaryotes (bacteria and cyanobacteria). Prokaryotes are single-celled organisms that lack a membrane-bound nucleus and usually lack membrane-bound organe...

cephalosporin

(Encyclopedia)cephalosporin sĕfˌəlōspôrˈĭn [key], any of a group of more than 20 antibiotics derived from species of fungi of the genus Cephalosporium and closely related chemically to penicillin. Cephalospo...

humus

(Encyclopedia)humus hyo͞oˈməs [key], organic matter that has decayed to a relatively stable, amorphous state. It is an important biological constituent of fertile soil. Humus is formed by the decomposing action ...

chitin

(Encyclopedia)chitin kītˈən [key], main constituent of the shells of arthropods. Chitin, a polysaccharide (see carbohydrate) analogous in chemical structure to cellulose, consists of units of a glucose derivativ...

disease

(Encyclopedia)disease, impairment of the normal state or functioning of the body as a whole or of any of its parts. Some diseases are acute, producing severe symptoms that terminate after a short time, e.g., pneumo...

hay fever

(Encyclopedia)hay fever, seasonal allergy causing inflammation of the mucous membranes of the nose and eyes. It is characterized by itching about the eyes and nose, sneezing, a profuse watery nasal discharge, and t...

infection

(Encyclopedia)infection, invasion of plant or animal tissues by microorganisms, i.e., bacteria, viruses, viroids, fungi, rickettsias, and protozoans. The invasion of body tissues by parasitic worms and other higher...

bioluminescence

(Encyclopedia)bioluminescence bīˌōlo͞oˌmĭnĕsˈəns [key], production of light by living organisms. Organisms that are bioluminescent include certain fungi and bacteria that emit light continuously. The dinof...

animal

(Encyclopedia)animal, any member of the animal kingdom (kingdom Animalia), as distinguished from organisms of the plant kingdom (kingdom Plantae) and the kingdoms Fungi, Protista, and Monera in the five-kingdom sys...

bald cypress

(Encyclopedia)bald cypress, common name for members of the Taxodiaceae, a small family of deciduous or evergreen conifers with needlelike or scalelike leaves and woody cones. Most species of the family are trees of...

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