Gastrovascular cavity
Encyclopedia
Gastro vascular cavity, as the name indicates, functions in both digestion
and the distribution of nutrients and particles to all parts of the body. Organisms belonging to two major phyla, the Cnidaria
and the Platyhelminthes, possess gastrovascular cavities.
The radially symmetrical cnidarians have a sac-like body in two distinct layers, the epidermis and gastrodermis, with a jellylike layer called the mesoglea
between. Extracellular digestion takes place within the central cavity of the sac-like body. This cavity has only one opening to the outside and, in most cnidarians, that is surrounded by tentacle
s which serve to capture prey.
Example: Digestion in hydra occurs in gastrovascular cavity.
Organisms with a gastrovascular cavity:
Digestion
Digestion is the mechanical and chemical breakdown of food into smaller components that are more easily absorbed into a blood stream, for instance. Digestion is a form of catabolism: a breakdown of large food molecules to smaller ones....
and the distribution of nutrients and particles to all parts of the body. Organisms belonging to two major phyla, the Cnidaria
Cnidaria
Cnidaria is a phylum containing over 9,000 species of animals found exclusively in aquatic and mostly marine environments. Their distinguishing feature is cnidocytes, specialized cells that they use mainly for capturing prey. Their bodies consist of mesoglea, a non-living jelly-like substance,...
and the Platyhelminthes, possess gastrovascular cavities.
The radially symmetrical cnidarians have a sac-like body in two distinct layers, the epidermis and gastrodermis, with a jellylike layer called the mesoglea
Mesoglea
Mesoglea is the translucent, inert, jelly-like substance that makes up most of the bodies of jellyfish, comb jellies and certain primitive sea creatures in the phyla Cnidaria and Ctenophora. It acts as the creatures' structural support in water, as they lack bones or cartilage, endo- or...
between. Extracellular digestion takes place within the central cavity of the sac-like body. This cavity has only one opening to the outside and, in most cnidarians, that is surrounded by tentacle
Tentacle
A tentacle or bothrium is one of usually two or more elongated flexible organs present in animals, especially invertebrates. The term may also refer to the hairs of the leaves of some insectivorous plants. Usually, tentacles are used for feeding, feeling and grasping. Anatomically, they work like...
s which serve to capture prey.
Example: Digestion in hydra occurs in gastrovascular cavity.
Organisms with a gastrovascular cavity:
- JellyfishJellyfishJellyfish are free-swimming members of the phylum Cnidaria. Medusa is another word for jellyfish, and refers to any free-swimming jellyfish stages in the phylum Cnidaria...
such as Aurelia - Sea anemoneSea anemoneSea anemones are a group of water-dwelling, predatory animals of the order Actiniaria; they are named after the anemone, a terrestrial flower. Sea anemones are classified in the phylum Cnidaria, class Anthozoa, subclass Zoantharia. Anthozoa often have large polyps that allow for digestion of larger...
s - CoralCoralCorals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...
s - Sea penSea penSea pens are colonial marine cnidarians belonging to the order Pennatulacea. There are 14 families within the order; they are thought to have a cosmopolitan distribution in tropical and temperate waters worldwide...
(also known as Sea Pansies) - Flatworms