What symmetry do organisms in this phylum have?
What level of organization are these organisms?
Polyp Body Type
Attached and sessile
Medusa Body Type
How many embryonic layers does this phylum have?
Two (diploblastic): endoderm and ectoderm
Three embryonic layers: endoderm, ectoderm and mesoderm
- Formed by endoderm.
- There is only one opening that serves as both the mouth and the anus.
Functions as both the digestive system and the transport system.
Glycoprotein holding the tissues together.
What are the three main classes of cnidaria?
- Go through both polyp and medusa stages.
- Medusae have velum, which is a shape-holding ring of tissue at the bottom of the exumbrella.
- Ex: Obelia
- Medusa stage only.
- Ex: Aurelia
- Polyp stage only.
- Solitary or colonial.
- Ex: Metridium
Name the parts of this image of Aurelia:
Filamentous organelles that are expelled from cnidocytes.
On the picture of the Aurelia life cycle, label the:
In the picture of Aurelia Ephyra label:
Define ocellus and statcyst.
- Ocellus: light sensation
- Statocyst: gravity sensation
What are polyp colonies called?
In the Obelia picture, label (and define):
- Hydranth: Feeding polyp
- Gonangium: Reproductive polyp
Corals that harbor symbiotic algae.
Small polyps, create huge coral reefs because they house their own food supply.
Corals that do not house ay photosynthetic symbionts.