Porifera, ctenophora, cnidaria Flashcards
What phylum do sponges belong too?
Porifera
What original cells do sponges contain?
Choanocytes
Where do water currents enter and leave a sponge?
Enter the ostia and leave via the osculum
What does the extracellular matrix of sponges contain?
Collagen
Often stiffened with spicules (of silica or calcium carbonate)
Sponges are loosely organised, no symmetry, muscles or nervous system
TRUE
How do sponges reproduce?
They are hermaphrodites
Sperm sent out via the osculum
Some asexually by budding
How do sponges feed?
Beating flagella draw water through sponge and choanocytes capture food particles.
Some are carnivorous- capture prey with spcules
Why are sponges important in medicine?
Cell recognition and rejection.
(Pass through a sieve cells dissociate an re-aggregate to form a new sponge)
Drugs
(Oxylipins , possible antibiotics and cancer drugs)
Why are they classed as ultimate recyclers?
Vital for coral reef health, soak up nutrients n sea water and turn into food
What are the three extant classes of sponges?
Desmospongia
Hexactinella
Calcarea
What are three examples of the phylum cnidaria?
Actinia, Aurelia, Hydra
What are the phylum ctenophora?
Comb jellies
What are the four extant classes of cnidaria
Hydrozoa
Anthozoa
Scyphozoa
Cubozoa
Two examples of hydrozoa
Hydra, Physalia
What features do ctenophora have? (3)
COMB JELLIES
150 spp
complete through gut
ctenes, cell with plates of cilia move animal
2 cell layers seperated by gelatinous mesogloea
What features do cndaria have? (3)
Cnidocytes - stinging cells Mouth connected to blind gastrovascular cavity Life cycle with two stage- Polyp: asexual may bud to form colonies Medusa: shed eggs and sperm into water
What features do Anthozoa have?
SEA ANEMONES, HARD CORALS, SOFT ROCKS
Lack medusa stage
Flower animals
Old polyps leave their calcareous skeletons behind
What features do hydrozoa have?
Hydra, Physalia
Polyp dominates life cycle
Most colonial
polyps specialised differently for different tasks
What are scyphozoa?
JELLYFISH
Cup shaped
Marine
Medusa large polyps little
What are cubozoa?
BOX JELLLYFISH
Square bell
Have eyes with retina, lens and iris
Some venomous
