zooid
Quick Summary
A zooid is one of the individuals that make up a compound organism, such as a bryozoan, coral, or siphonophore colony. These individuals are produced asexually through budding and remain connected to form a larger organism. Zooids are typically very small, rarely exceeding one millimeter in length.123
While the exact structure varies, zooids generally share a basic plan. They possess an external skeleton, tentacles called a lophophore for feeding, and a digestive system. They lack separate respiratory, circulatory, and excretory systems. In some species, zooids can be specialized for different functions, such as defense or reproduction, a phenomenon known as polymorphism. These colonies, though composed of many zooids, function as a single integrated organism with some level of coordinated behavior.34
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moss animal…of numerous connected units called zooids (hence the term Polyzoa, which means “many animals”). Individual zooids are usually no more than one millimetre (0.04 inch) long, although colonies of some species can exceed 0.5 metre (about 20 inches) in diameter. Until the mid-18th century, bryozoans, like corals, were regarded as…
Read More…of numerous connected units called zooids (hence the term Polyzoa, which means “many animals”). Individual zooids are usually no more than one millimetre (0.04 inch) long, although colonies of some species can exceed 0.5 metre (about 20 inches) in diameter. Until the mid-18th century, bryozoans, like corals, were regarded as…
Read More- moss animalAnnotated classification
CheilostomataZooids generally shaped like a flat box, walls calcified; orifice frontal, closed by a hinged operculum; specialized zooids commonly present; embryos often developing in ooecia (brood chambers); Upper Jurassic to present; about 70 families, 2,750 species.Classification of bryozoans began in 1837 when…
Read MoreCheilostomataZooids generally shaped like a flat box, walls calcified; orifice frontal, closed by a hinged operculum; specialized zooids commonly present; embryos often developing in ooecia (brood chambers); Upper Jurassic to present; about 70 families, 2,750 species.Classification of bryozoans began in 1837 when…
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