Kingdom Animalia Phylum Cnidaria Characteristics n Radial or





















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Kingdom Animalia Phylum Cnidaria

Characteristics n Radial or biradial symmetry n Diploblastic organization n Mesoglea between epidermis and gastrodermis n Gastrovascular cavity n Nerve net n Cnidocytes – used in defense and feeding

Reproduction/Life Cycle n Can be monoecious or dioecious n Alternate generations between polyp and medusa form n Polyp – asexual and sessile n Medusa – dioecious and free swimming

Reproduction Cont’d n Planula – Cnidaria larvae n Polyps are produced by budding or planula n Medusae formed by budding from a polyp body wall

Feeding n Use cnidocytes to stun or kill prey n Tentacles contract to bring food to mouth n Food is digested in gastrovascular cavity

Support and Locomotion n Hydrostatic Skeleton n Some classes have longitudinal muscles that aid in movement n Polyps – somersault, inchworm, glide on base, and walk on their tentacles n Medusae – swim and float

Classification n. Class Hydrozoa n. Class Scyphozoa n. Class Cubozoa n. Class Anthozoa

Class Hydrozoa n Mostly marine, but the only class with freshwater members! n Alternate generations n Mostly colonial polyps

Obelia n Gastrozooid – feeding polyp formed from planula larvae n Grows through budding into more gastrozooids n Gonozooid – reproductive polyp that forms medusa by budding n Medusae then reproduce sexually

Gastrozooid Gonozooid

Gonionemus n Medusa predominant n Has a velum (shelf-like lip that projects inward) n Velum creates jet propulsion n Mouth at end of a manubrium n Nerve ring that coordinates swimming movements n Statocyst – responds to gravity


Hydra n Freshwater n Polyps only, no medusae n Testes form sperm by meiosis n Ovaries form one egg each

Physalia n Portuguese man-of- war n Colonial n Cannot swim n Cnidocytes in tentacles are lethal to small vertebrates and dangerous to humans

Class Scyphozoa n All marine n “True Jellyfish” – medusa dominant

Stinging Nettle, Mastigias

Aurelia n Gastrodermal cells have cilia to circulate food n Feeds on plankton n Rhopalia – chemoreceptors n Lappets – touch receptors n Statocysts – gravity sensors n Ocelli - photoreceptors

Class Cubozoa n Medusae are cuboidal n Polyps are reduced or absent n Tentacles hang from corners

Class Anthozoa n Polyps only, no medusae n Mouth has a pharynx n Gastrovascular cavity is divided into sections n Sexual and asexual reproduction

Sea Anemones

Corals
Physalia diagram
Kingdom animalia phylum cnidaria
Kingdom animalia phylum chordata
Family leporidae kingdom
Kingdom: animalia phylum: arthropoda class: insecta
Kingdom animalia phylum arthropoda
Kingdom animalia phylum chordata
Sea anemone phylum and class
Phylum cnidaria general characteristics
General characteristics of cnidaria
Brittle stars phylum
Osteichtheyes
Characteristics of animals
Old kingdom middle kingdom new kingdom
Old kingdom middle kingdom new kingdom
Old kingdom middle kingdom new kingdom
Old kingdom middle kingdom new kingdom
Pedalium
Cnidaria and ctenophora
Cnidaria subkingdom
Filo cnidaria
Jellyfish