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NOAA Coral Reef Conservation Program, National Oceanic and Atmospheric Administration, U.S. Department of Commerce
The point in the orbit of the Moon or man-made satellite farthest from the Earth; the point in the orbit of a satellite farthest from its companion body.
Industry:Natural environment
The terminal part of a eukaryotic chromosome. These specialised structures are involved in the replication and stability of linear DNA molecules. In vertebrate cells, each telomere consists of thousands of repetitive copies of the same DNA sequence. Telomeres shorten each time a cell divides; when one or more telomeres reaches a minimum critical length, cell division stops, signaling cell senescence. This mechanism limits the number of times a cell can divide .
Industry:Natural environment
The Kingdom composed of prokaryotic organisms. They have a cell wall, and lack both membrane-bound organelles and multicellular forms. The Archaebacteria, the most ancient of this Kingdom, are so different that they may belong to a separate kingdom. Monera include the cyanobacteria and eubacteria.
Industry:Natural environment
A central cell structure that contains the chromosomes, and as such, controls the activities of the cell; the center of an atom, containing protons, neutrons, and most of the mass.
Industry:Natural environment
A fish which broods or protects the eggs or young by taking them into the mouth cavity.
Industry:Natural environment
A marine gastropod, many of which have lost or reduced their shell, mantle and gills.
Industry:Natural environment
A preparation that contains an antigen, consisting of dead or weakened whole or parts of disease-causing organisms, that is used to confer immunity against the disease that the organisms cause. Vaccine preparations can be natural, synthetic or derived by recombinant DNA technology.
Industry:Natural environment
A stage of embryonic development of animals near the end of cleavage (cell division), but before gastrulation. In animals where cleavage involves the whole egg, the blastula usually consists of a hollow ball of cells (blastomeres) surrounding a fluid-filled central cavity, the blastocoel.
Industry:Natural environment
A waste product of metabolism eliminated via the kidneys. In elasmobranchs (sharks, rays, skates), urea is found in the blood where it helps to maintain osmotic balance.
Industry:Natural environment
