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Main features of chordates and explanation of types of chordates.......no spam plz it is urgent |
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Answer» These characteristics are only present during embryonic DEVELOPMENT in some chordates.The notochord provides skeletal support, gives the phylum its name, and develops into the vertebral column in vertebrates.The DORSAL hollow nerve cord develops into the central nervous system: the brain and spine.Pharyngeal slits are openings in the pharynx that develop into gill arches in bony fish and into the JAW and inner ear in terrestrial animals.The post-anal tail is a skeletal extension of the posterior end of the body, being absent in humans and apes, although present during embryonic development.Key Termsnotochord: a flexible rodlike structure that forms the main support of the body in the lowest chordates; a primitive spinenerve cord: a dorsal tubular cord of nervous tissue above the notochord of a chordatepharyngeal slit: filter-feeding ORGANS found in non-vertebrate chordates (lancelets and tunicates) and HEMICHORDATES living in aquatic environments |
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