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dry rot

(Encyclopedia)dry rot, fungus disease that attacks both softwood and hardwood timber. Destruction of the cellulose causes discoloration and eventual crumbling of the wood. This frequently results in the collapse of...

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...

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...

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...

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 ...

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...