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schistosomiasis

(Encyclopedia)schistosomiasis bĭlˌhärzīˈəsĭs [key], or snail fever, parasitic disease caused by blood flukes, trematode worms of the genus Schistosoma. Three species are human parasites: S. mansoni, S. japon...

screamer

(Encyclopedia)screamer, common name for gregarious, aquatic birds comprising three species in the family Anhimidae. Although they are related to the ducks and geese, they do not resemble them in outward appearance....

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 ...

pistil

(Encyclopedia)pistil pĭsˈtĭl [key], one of the four basic parts of a flower, the central structure around which are arranged the stamens, the petals, and the sepals. The pistil is usually called the female repro...

rhythm, biological

(Encyclopedia)rhythm, biological, or biorhythm, cyclic pattern of physiological changes or changes in activity in living organisms, most often synchronized with daily, monthly, or annual cyclical changes in the env...

ovary

(Encyclopedia)ovary, ductless gland of the female in which the ova (female reproductive cells) are produced. In vertebrate animals the ovary also secretes the sex hormones estrogen and progesterone, which control t...

fats and oils

(Encyclopedia)fats and oils, group of organic substances that form an important part of the diet and also are useful in many industries. The fats are usually solid, the oils generally liquid at ordinary room temper...

microscope

(Encyclopedia)CE5 Compound microscope microscope, optical instrument used to increase the apparent size of an object. The electron microscope, which is not limited by the powers of optical lenses and light,...

deer

(Encyclopedia)deer, ruminant mammal of the family Cervidae, found in most parts of the world except Australia. Antlers, solid bony outgrowths of the skull, develop in the males of most species and are shed and rene...

onion

(Encyclopedia)onion, plant of the family Liliaceae (lily family), of the same genus (Allium) as the chive (A. schoenoprasum), garlic (A. sativum), leek (A. porrum), and shallot (A. ascalonium). These plants are cha...