Animalscaretips
Two different types of polyps exist together in the colonies of Obelia, each serving different primary purposes.
- What are the two types of polyps in Obelia?
- Does Obelia have polyp?
- What is the feeding polyp in Obelia called?
- What is difference between polyp and medusa?
- What is polyp and medusa?
- What is obelia colony?
- How do you identify obelia?
- What are the function of polyp of obelia?
- Is Metagenesis seen in Aurelia?
- What is the function of Gastrozooids in polyp?
- How does a polyp turn into a Medusa?
- Is sea anemone a polyp or medusa?
- What is medusa of Obelia?
What are the two types of polyps in Obelia?
The colonial sessile form of Obelia geniculata has two types of polyps: gastrozooids, which are adapted for capturing prey, and gonozooids, which asexually bud to produce medusae.
Does Obelia have polyp?
Obelia is a genus of hydrozoans, a class of mainly marine and some freshwater animal species that have both polyp and medusa stages in their life cycle. Hydrozoa belongs to the phylum Cnidaria, which are aquatic (mainly marine) organisms that are relatively simple in structure. Obelia is also called sea fur.
What is the feeding polyp in Obelia called?
Gastrozooids, or hydranths, are the feeding polyps. They have a mouth surrounded by stinging tentacles, giving them a flower-like appearance, and are responsible for capturing and consuming food. Food is digested in the gastrovascular cavity and provided to the rest of the colony.
What is difference between polyp and medusa?
Sessile structures are called polyps while the swimming forms are called medusa. The key difference between polyp and medusa is that polyp is a fixed, cylindrical structure, representing the asexual stage and medusa is a free swimming, umbrella-like structure, representing the sexual stage.
What is polyp and medusa?
There are two basic cnidarian body shapes: a polyp form, which is attached to a surface; and an upside-down free-floating form called a medusa. Some cnidarians change form at different phases of their life cycle, while others remain in one form for their entire life.
What is obelia colony?
Obelia colony is a mesh of highly branched structure where horizontal hydrorhiza is attached to the substratum and has the vertical branches or hydrocauli (about 2.5 cm in length) that bear zooids. Both hydrocaulus and hydrorhiza are hollow tubes.
How do you identify obelia?
[Obelia-medusa] Umbrella flat, with velum minute or lacking (authorities differ). Stomach short, with quadrangular base, without peduncle; mouth with four short simple lips. Radial canals four, straight; they and ring canal narrow, the latter hard to discern.
What are the function of polyp of obelia?
Obelia polyps (= zooids) are dimorphic, there being two types in the colony. Gastrozooids are responsible for feeding, which they accomplish by capturing and ingesting zooplankton. Gonozooids are reproductive and produce medusae by asexual budding.
Is Metagenesis seen in Aurelia?
No metagenesis is observed in the case of Aurelia.
What is the function of Gastrozooids in polyp?
The role of gastrozooids, which have mouths surrounded by tentacles tipped with stinging cells, is to capture and consume food. The reproductive duties, however, belong to the gonzooids, which create the successive generation, small jellyfish known as medusae, via budding.
How does a polyp turn into a Medusa?
In organisms that exhibit both forms, such as members of the cosmopolitan genus Obelia, the polyp is the asexual stage and the medusa the sexual stage. In such organisms the polyp, by budding, gives rise to medusae, which either detach themselves and swim away or remain permanently attached to the polyp.
Is sea anemone a polyp or medusa?
Unlike jellyfish, sea anemones do not have a medusa stage in their life cycle. A typical sea anemone is a single polyp attached to a hard surface by its base, but some species live in soft sediment and a few float near the surface of the water.
What is medusa of Obelia?
A fully grown Obelia medusa is a radially symmetrical tiny umbrella, measuring 1 or 2 mm in diameter. Medusa is carnivorous and feeds on planktons.
