Lophophorates

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Transcript Lophophorates

CHAPTER 19 LOPHOPHORATES

PHORONIDA, BRACHIOPODS, BRYOZOANS

Phylum Phoronida

Marine organisms that live in sediments

Phoronida characters

•Filter feeding •Do not move •Cilia create current to bring particles to tentacles; then to mouth •Metanephridia •Blood vessel contains blood (w/ hemoglobin)

Phoronida

• Hermaphroditic • Sperm released from nephridia, collected by other individual • Embryo = actinotroch

Phylum Brachiopoda

• = “arm foot” • 2-valve shell • Marine lophophorates

Phylum Brachiopoda characters

• At poles or deep marine, permanently attached to substrate • Metanephridia • Circulatory system w/heart and contractile vessels - no blood pigment

Brachiopoda

• Sperm, eggs discharged from nephridiopores • Fert external

Phylum Bryozoa

• Moss animals • Colonial animals that attach to substrate • Marine (5000 species) and freshwater (50) • Fossils (15,000)

Bryozoa

• Secrete a covering around body • Asexual repro, hermaphroditic

Bryozoa

•Sperm into coelomic cavity, released from openings in tentacles •Neighbors collect sperm for fert.

•Some brood embryos

Digestion

• Phoronids, bryozoans: U-shaped • Brachiopods: U-shaped one way tract

Nervous systems

• Ring at base of lophophore, around esophagus, or by pharynx • Mechanoreceptors and chemoreceptors scattered