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tryptophan

(Encyclopedia)CE5 tryptophan trĭpˈtəfăn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essent...

pharming

(Encyclopedia)pharming färˈmĭng [key], the use of genetically altered livestock, such as cows, goats, pigs, and chickens, to produce medically useful products. In pharming, researchers first create hybrid genes ...

fungal infection

(Encyclopedia)fungal infection, infection caused by a fungus (see Fungi), some affecting animals, others plants. Serious damage is done to crops each year by fungal infections of plants such as smuts, rusts, ergo...

marine biology

(Encyclopedia)marine biology, study of ocean plants and animals and their ecological relationships. Marine organisms may be classified (according to their mode of life) as nektonic, planktonic, or benthic. Nektonic...

allergy

(Encyclopedia)allergy, hypersensitive reaction of the body tissues of certain individuals to certain substances that, in similar amounts and circumstances, are innocuous to other persons. Allergens, or allergy-caus...

intestine

(Encyclopedia)intestine, muscular hoselike portion of the gastrointestinal tract extending from the lower end of the stomach (pylorus) to the anal opening. In humans this fairly narrow (about 1 in./2.5 cm) tubelike...

autoimmune disease

(Encyclopedia)autoimmune disease, any of a number of abnormal conditions caused when the body produces antibodies to its own substances. In rheumatoid arthritis, a group of antibody molecules called collectively RF...

paramecium

(Encyclopedia)paramecium parəmēˈsĭəm [key], unicellular organism of the genus Paramecium, of the ciliate phylum Ciliophora found in freshwater throughout the world. Like other protozoans, paramecia, previously...

poisonous plant

(Encyclopedia)poisonous plant, any plant possessing a property injurious to man or animal. Plants may be poisonous to the touch (e.g., poison ivy, poison sumac), or orally toxic (e.g., poison hemlock, deadly amanit...

immunity

(Encyclopedia)immunity, ability of an organism to resist disease by identifying and destroying foreign substances or organisms. Although all animals have some immune capabilities, little is known about nonmammalian...