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Lycopodiophyta

(Encyclopedia)Lycopodiophyta līˌkōpōˌdēŏfˈətə [key], division of the plant kingdom consisting of the organisms commonly called club mosses and quillworts. As in other vascular plants, the sporophyte, or s...

United Nations Conference on Environment and Development

(Encyclopedia)United Nations Conference on Environment and Development (UNCED) or Earth Summit, an 11-day meeting held in June, 1992, in Rio de Janeiro, Brazil, to discuss the global conflict between economic devel...

Alzheimer's disease

(Encyclopedia)Alzheimer's disease ălsˈhīˌmərz, ôls– [key], degenerative disease of nerve cells in the cerebral cortex that leads to atrophy of the brain and senile dementia and, ultimately, death. The disea...

immunology

(Encyclopedia)immunology, branch of medicine that studies the response of organisms to foreign substances, e.g., viruses, bacteria, and bacterial toxins (see immunity). Immunologists study the tissues and organs of...

horseshoe crab

(Encyclopedia)horseshoe crab, large, primitive marine arthropod of the family Limulidae, related to the spider and scorpion and sometimes called a king crab (a name also used for the largest of the edible true crab...

anemia

(Encyclopedia)anemia ənēˈmēə [key], condition in which the concentration of hemoglobin in the circulating blood is below normal. Such a condition is caused by a deficient number of erythrocytes (red blood cell...

bee

(Encyclopedia)bee, name for flying insects of the superfamily Apoidea, in the same order as the ants and the wasps. Bees are characterized by their enlarged hind feet, typically equipped with pollen baskets of stif...

Edwards, Sir Robert Geoffrey

(Encyclopedia)Edwards, Sir Robert Geoffrey, 1925–2013, British physiologist, Ph.D. Edinburgh Univ., 1955. In 1963 he became a research fellow at Cambridge. He was associated with the university until his death, a...

anticoagulant

(Encyclopedia)anticoagulant ănˌtēkōăgˈyələnt [key], any of several substances that inhibit blood clot formation (see blood clotting). Some anticoagulants, such as the coumarin derivatives bishydroxycoumarin...

gall bladder

(Encyclopedia)CE5 Gall bladder gall bladder, small pear-shaped sac that stores and concentrates bile. It is connected to the liver (which produces the bile) by the hepatic duct. When food containing fat reaches...