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Maximilian I, 1573–1651, elector and duke of Bavaria

(Encyclopedia)Maximilian I, 1573–1651, elector (1623–51) and duke (1597–1651) of Bavaria, one of the outstanding figures of the Thirty Years War and an ardent supporter of the Counter Reformation. His occupat...

phosphorylation

(Encyclopedia)phosphorylation, chemical process in which a phosphate group is added to an organic molecule. In living cells phosphorylation is associated with respiration, which takes place in the cell's mitochondr...

Pachycephalosaurus

(Encyclopedia)Pachycephalosaurus păkˌĭsĕfˌəlōsôrˈəs [key] [Gr., = thick-headed lizard], bipedal herbivorous dinosaur of the late Cretaceous period, approximately 68–65 million years ago. Its disting...

horizon

(Encyclopedia)horizon, in astronomy, roughly circular line bounding an observer's view of the surface of the earth where the sky and earth seem to meet. This is the visible horizon. At sea the visible horizon is a ...

weathering

(Encyclopedia)weathering, collective term for the processes by which rock at or near the earth's surface is disintegrated and decomposed by the action of atmospheric agents, water, and living things. Some of these ...

Homo erectus

(Encyclopedia)Homo erectus hōˈmō ērĕkˈtəs [key], extinct hominin living between 1.6 million and 250,000 years ago, possibly as late as c.110,000 years ago. Homo erectus is thought to have evolved in Africa f...

alkene

(Encyclopedia)CE5 Alkenes alkene ălˈkēn [key], any of a group of aliphatic hydrocarbons whose molecules contain one or more carbon-carbon double bonds (see chemical bond). Alkenes with only one double bond h...

Triassic period

(Encyclopedia)Triassic period trīăsˈĭk [key], first period of the Mesozoic era of geologic time (see Geologic Timescale, tablegeologic timescale, table) from 205 to 250 million years ago. Throughout the Triassi...

trilobite

(Encyclopedia)CE5 Dorsal view of a trilobite trilobite trīˈləbītˌ [key], subphylum of the phylum Arthropoda that includes a large group of extinct marine animals that were abundant in the Paleozoic era. Th...