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Haldane, John Scott

(Encyclopedia)Haldane, John Scott, 1860–1936, British scientist, b. Edinburgh; father of John Burdon Sanderson Haldane. He made many important contributions to mine safety, investigating principally the action of...

adenoids

(Encyclopedia)adenoids ădˈənoidzˌ [key], common name for the pharyngeal tonsils, spongy masses of lymphoid tissue that occupy the nasopharynx, the space between the back of the nose and the throat. Normally the...

cytochrome

(Encyclopedia)cytochrome sīˈtəkrōmˌ [key], protein containing heme (see coenzyme) that participates in the phase of biochemical respiration called oxidative phosphorylation. Cytochromes act as carriers of hydr...

swim bladder

(Encyclopedia)swim bladder, large, thin-walled sac in some fishes that may function in several ways, e.g., as a buoyant float, a sound producer and receptor, and a respiratory organ. The swim bladder, or air bladde...

tonsils

(Encyclopedia)tonsils, name commonly referring to the palatine tonsils, two ovoid masses of lymphoid tissue situated on either side of the throat at the back of the tongue. The pharyngeal tonsils, or adenoids, are ...

fumaric acid

(Encyclopedia)fumaric acid fyo͞omărˈĭk [key] or trans-butenedioic acid, HO2CCH=CHCO2H, unsaturated dicarboxylic acid that melts at 287℃. Maleic acid, or cis-butenedioic acid, is a geometric isomer of fumaric ...

trachea

(Encyclopedia)trachea trāˈkēə [key] or windpipe, principal tube that carries air to and from the lungs. It is about 41⁄2 in. (11.4 cm) long and about 3⁄4 in. (1.9 cm) in diameter in the adult. It extends fr...

first aid

(Encyclopedia)first aid, immediate and temporary treatment of a victim of sudden illness or injury while awaiting the arrival of medical aid. Proper early measures may be instrumental in saving life and ensuring a ...

nerve gas

(Encyclopedia)nerve gas, any of several poison gases intended for military use, e.g., tabun, sarin, soman, and VX. Nerve gases were first developed by Germany during World War II but were not used at that time. The...

sand dollar

(Encyclopedia)sand dollar, common name for a marine animal in the same phylum as the starfish (see sea star). The sand dollar has a rigid, flattened, disk-shaped test, or shell, made of firmly united plates lying j...

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