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ectoderm

(Encyclopedia)ectoderm, layer of cells that covers the surface of an animal embryo after the process of gastrulation has occurred. This outer layer, together with the endoderm, or inner layer, is present in all ear...

Ectoprocta

(Encyclopedia)CE5 Bugula, a moss animal, representative of the phylum Ectoprocta Ectoprocta ĕkˌtəprŏkˈtə [key], phylum of sessile, colonial aquatic animals (commonly known as moss animals or oryonzoans). ...

hamster

(Encyclopedia)hamster, Old World rodent, related to the voles, lemmings, and New World mice. There are many hamster species, classified in several genera. All are solitary, burrowing, nocturnal animals, with chunky...

Katmai National Park and Preserve

(Encyclopedia)Katmai National Park and Preserve kătˈmī [key], at the northern end of the Alaska Peninsula on Shelikof Strait, S Alaska, comprising Katmai National Park (3,674,530 acres/1,487,664 hectares) and an...

phenylalanine

(Encyclopedia)CE5 phenylalanine fĕnˌəlălˈənēnˌ [key], organic compound, one of the 22 α-amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of ...

water mold

(Encyclopedia)water mold, common name for a group of multinucleated organisms that superficially resemble fungi but are now recognized as having an independent evolutionary lineage and are placed in the kingdom Pro...

zoology

(Encyclopedia)zoology, branch of biology concerned with the study of animal life. From earliest times animals have been vitally important to man; cave art demonstrates the practical and mystical significance animal...

bichir

(Encyclopedia)bichir bĭchˈər [key], common name for African freshwater fishes as of the family Polypteridae, and particularly for those of the genus Polypterus. Bichirs are among the most primitive of the ray-fi...

bone marrow

(Encyclopedia)bone marrow, soft tissue filling the spongy interiors of animal bones. Red marrow is the principal organ that forms blood cells in mammals, including humans (see blood). In children, the bones contain...

Hittite art and architecture

(Encyclopedia)Hittite art and architecture, works of art and structures created by the ancient Hittites The principal architectural remnant of the Hittite civilization is at Boğazköy, where temple structures ...