Is Obelia a Cnidaria?
(June 2013) Obelia is a genus of hydrozoans, which consists mainly of marine and some freshwater animal species and have both the polyp and medusa stages in their life cycle. The genus belongs to the phylum Cnidaria, which are all aquatic and mainly marine organisms that are relatively simple in structure.
What type of animal is Obelia?
Obelia, genus of invertebrate marine animals of the class Hydrozoa (phylum Cnidaria). The genus, widely distributed in all the oceans, is represented by many species. The animal begins life as a polyp”a tentacled, stalklike form resembling a small sea anemone attached to the ocean bottom or some other solid surface.
Is Obelia a hydrozoan?
Obelia is a typical example of a marine, colonial hydrozoan. Like most hydrozoans it has both polyp and medusa stages. Obelia occurs as a delicate whitish or light brown, almost fur-like growth on seaweeds or timber.
What is an Obelia and how is it formed?
All obelia begin as polyps that are connected to a solid surface such as the ocean floor. With time the polyp grows and forms a colony which is made up of hydranth and gonanium units. The colony feeds through the hydranth portion that consists of mouths and stomachs, enabling the colony to feed.
What are cnidarians?
Cnidarians are all invertebrates that fall under the Phylum Cnidaria of the animal kingdom. Phylum Cnidaria is also known as the Phylum Coelenterata. They are all radially symmetrical simple organisms that are found only in aquatic habitats. Cnidarians include over 11,000 known species.
Are Obelia different forms of the same organism?
Though they might appear like they are different organisms to an observer, they are all forms of the same organism as they change forms in their different stages of a very complex life cycle. The Obelia genus belongs to the invertebrates marine animals and can be found in all the oceans of planet earth.
What are the two forms of Obelia?
Through its life cycle, Obelia take two forms: polyp and medusa. They are diploblastic, with two true tissue layers “ an epidermis (ectodermis) and a gastrodermis (endodermis), with a jelly-like mesoglea filling the area between the two true tissue layers.
What are the two Obelia reproduction stages?
Let us delve into the two obelia reproduction stages below: The Polyp Reproduction Stage – The polyp stage is the first stage in the life cycle of an obelia. All obelia begin as polyps that are connected to a solid surface such as the ocean floor. With time the polyp grows and forms a colony which is made up of hydranth and gonanium units.
What is the structure and locomotion of Obelia?
In this article we will discuss about the structure and locomotion of obelia. Obelia is a marine colony of hydroid organisms. It is a moss like animal found on submerged rocks or sea weeds, in shallow water off the sea coast. It may be regarded as a Hydra which has undergone repeated budding but the buds have not separated from the parent.
Where is Obelia found?
Obelia is sedentary, marine and colonial form. It is found up to the depth of 80 meters. It occurs in both asexual and sexual forms. It grows in intertidal rock pools and at the extreme low water of spring tides. Obelia is also called as Sea fur.