Cnidaria Flashcards
Grade
Phylum
Classes
Grade- Eumetzoa
Phylum- Cnidaria
Classes- Hydrozoa, scyphozoa, anthozoa
Characteristics
Dimorphism and polymorphic
Stages
Polyp- benthic
Medusa— planktonic
Mesogla- jelly part
Class Scyphozoa
Genus-
Genus- Aurelia (regular jelly)
Class Anthozoa
Genus-
Genus- Metridium
Sea anemones
No Medusa stage only polyp
Class Hydrozoa
Genus-
Genus-
Obelia( colonial)
Hydra (solitary)
Physalia (man of war- colonial)
Class scyphozoa
Genus Aurelia
Aurelia life cycle
- planula larva
- Scyphistoma
- Strobila
- Ephyra
- Adult Medusa
Stinging mechanism
Cnidocytes- form into nematocytes/cnidae
Eversion
Firing of the nematocyte
Cell types In Gastrovascular cavity of cnidarians
Gland cells
Nutritive-muscle cell
Gland cell
In gastroermis, secrete enzymes to break food body into soup
Nutritive muscle cells
Phagocytize bits to digest in the food vacuole
Dermal layers
Epidedermal
Gastrodermal
Epidermal layer
Contractile myofibrils (extra cellular) attached at the NMCells (intracellular)
Gastrodermal layer
Circular myofibrils and longitudinal myofibrils
Circular myofibrils
Make the Anthozoa taller more water fills the cavity
Shape determined by water because…
Incompressible mass of fluid
Anthozoa
Can be colonial, use acorhagi for fighting, have super strong nematocysts and fighting tentacles
Caste system
Repro in middle, fighters on outside
Achrohagi in Anthozoa
Tentacles used for Fighting
Nematocysts relationship
Ready but not fired, curled up inside capsules that are within the cnidocyte. Use once have to mature a new one
Body characteristic
Radical body symmetry No cephalization( oral and aboral end) Gastrovascular cavity with 1 opening
Cnidocytes
Stinging cells found in epidermis of tentacles
Corals and zooxanthelle
Bleaching no zooxanthelle
Mutualism, lives in gastrodermis- photosynthesis converts to organic food matter for coral then coral converts to CO2 for photosynthesis and again
