Medusa is a type of body form found in cnidarians. Describe the life cycle and the mode of life in... Phylum Nematoda: Classes, Characteristics & Examples, Phylum Porifera: Definition, Characteristics & Examples, Alternation of Generations: The Gametophyte and Sporophyte, Kingdom Protista: Definition, Characteristics & Examples, Cell Membrane: Functions, Role & Structure, Middle School Earth Science: Tutoring Solution, FTCE Physics 6-12 (032): Test Practice & Study Guide, ILTS Science - Chemistry (106): Test Practice and Study Guide, TExES Health EC-12 (157): Practice & Study Guide, Praxis Biology and General Science: Practice and Study Guide, Praxis Biology (5235): Practice & Study Guide, SAT Subject Test Biology: Practice and Study Guide, Human Anatomy & Physiology: Help and Review, High School Biology: Homework Help Resource, UExcel Pathophysiology: Study Guide & Test Prep, Biological and Biomedical The medusa, when free swimming, is popularly known as a jellyfish Examine the live specimens of Hydra fuscus (brown hydra) and Hydra viridens (green hydra has symbiotic algae). Jellyfish, on the other hand, exhibit only the medusa stage, while members of the genus Hydra exhibit the polyp form. Like the difference between a pumpkin and a human head. Get a free answer to a quick problem. Other creatures start life as fee-swimming medusa, then settle and become polyps. Hydra exists in both forms: Polyp and Medusa. Create your account. Most hydrozoans alternate between a polyp and a medusa stage — they spend part of their lives as "jellyfish" which are hard to distinguish from scyphozoan jellyfish. All other trademarks and copyrights are the property of their respective owners. This is the beginning of the rest of the animal kingdom, the eumetazoa, or "true animals" (we eumetazoans are a little biased). They remain as organisms, throughout their lives. 1. answered 07/26/16. It also has a vast and greater majority of species in both the ecosystems. Polyp and medusa body shapes Next. The two forms are similar in construction; both consist of a cylindrical body surrounding a digestive cavity, with a single opening, the mouth, at one end. If not then please post again and I shall try to explain. This polyp is also called “scyphistoma”. Under harsh living conditions and starvation, hydra reproduces sexually. The polyp is a sessile, or nonmotile, organism; well-known solitary polyps are the sea anemone and the freshwater hydra. Hydras are sessile animals, but the polyps are able to move and change their location. • Hydra does not have medusa form in their life cycle, whereas Obelia has both forms; polyp and medusa. The upper, or free, end of the body, which is hollow and cylindrical, typically Hydra exists in both forms: Polyp and Medusa. Most hydras have a polyp and medusa stage. - Solitary and Colonial. Like porifera, the hydra has two layers of cells separated by a jelly-like layer. • Hydra is a solitary species and lives attached to substrates, whereas Obelia is a colonial species and lives as polyps in an interconnected branching network. In the phylum Cnidaria, which includes jellyfish and sea anemones, polyp and medusa are two different stages of the life cycle. Life cycle: Cnidarians alternate between the polyp and medusa life forms. Thin layers called endoderm and ectoderm line the outside and inside, respectively; between these is a layer of jellylike material, called mesoglea, of v… Two distinct body plans are found in Cnidarians: the polyp or tuliplike “stalk” form and the medusa or “bell” form. Der Stamm: Cnidaria besteht aus vier Klassen: Hydrozoa (Hydra, Siphonophores), Scyphozoa (Quallen), Cubozoa (Kastengelees) und Anthozoa (Seeanemonen, Korallen, Seekugelschreiber).Anthozoa ist sessile. These forms are dependent upon nutritional content of the living environment. Hydras are sessile animals, but the polyps are able to move and change their location. Main Difference. The polyp may be solitary, as in the sea anemone, or colonial, as in coral, and is sessile (attached to a surface). These forms are dependent upon nutritional content of the living environment. Medusa is the adult and sexual form whereas Polyp is juvenile and asexual form. Examine the live specimens of Hydra fuscus (brown hydra) and Hydra viridens (green hydra has symbiotic algae). Genus Hydra. Obelia’s sexual stage is medusa. Eumetazoans have tissues that develop from the germ layers of the embryo, and there are two basic body styles that are defined by our symmetry, either radial or bilateral. Corals, sea anemones and jellyfish belong to a group of animals called cnidarians. answer! In hydra, the medusa stage is absent and polyps reproduce both sexually and asexually. The polyp is a sessile, or nonmotile, organism; well-known solitary polyps are the sea anemone and the freshwater hydra. Polyp: Medusa: Polyp is a sessile life cycle stage of the Cnidaria phylum. Polyp, in zoology, one of two principal body forms occurring in members of the animal phylum Cnidaria. 3. There can be variations in the structure but the similarity in shape is the presence of tentacular structure and the outer structure. Under harsh living conditions and starvation, hydra reproduces sexually. RNDr. Hydra does not have a medusa form and reproduces sexually by the formation of gametes. Hydrozoa: More on Morphology: Most hydrozoans show the same alternation between polyp and medusa phases that the Scyphozoa, or "true" jellyfish, have.A fertilized egg develops into a sessile polyp, which buds asexually and eventually buds off one or more medusae.The medusa produce eggs and sperm, reproduce sexually, and thus the cycle is repeated. Sea anemones are solitary polyps that reproduce sexually to form new polyps. Polyp Phase. The medusa, when free swimming, is popularly known as a jellyfish. Lv 5. Class Hydrozoa. However, Hydra is not typical of the Hydrozoa as a whole. hydra) have no medusae. Start here or give us a call: (312) 646-6365. Medusa and polyp are the two body forms of cnidarians that alter through generations. They have a simple body consisting of a central gut cavity surrounded by tentacles. Hope this explains you the life-cycle. Earn Transferable Credit & Get your Degree. Two distinct body plans are found in Cnidarians: the polyp or tuliplike “stalk” form and the medusa or “bell” form. A great many hydrozoans are also colonial. Corals, sea anemones and jellyfish belong to a group of animals called cnidarians. So it catches food from prey that swim past them. The body wall is composed of three layers of tissue. Some have no polyp stages and some (e.g. Jellyfish, on the other hand, exhibit only the medusa stage, while members of the genus Hydra exhibit the polyp form. They develop into medusa again when food sources are scarce and temperature in unfavorable for asexual reproduction. Hauptunterschied - Polyp gegen Medusa. Simply, the modes of living are different between a medusa and a polyp. Hydra) are single; others (e.g. There are many differences between medusae and polyps with regard to the shapes, sizes, and functions. Medusae. Hydra (class specimen) has no POLYP form. Body saucer shaped, umbrella like with a reduced stalk (Jellyfish). 0 0. Become a Study.com member to unlock this Simply, the modes of living are different between a medusa and a polyp. Obelia is a form of hydrozoans that have branched stalks. Hydras are up to 30 mm long solitary polyp animal, while Obelia is up to 25 cm long colony of interconnected polyps. Body attached below so that manubrium is … in the tentacles Body cylindrical with a long stalk (Hydra). Many other members of the class Hydrozoa, however, change from a polyp … It usually reproduces asexually only in the medusa form by the formation of gametes. Hydrozoa have a variety of life cycles. Polyp phase is also one of the structural differences between Obelia and jellyfish. Hydra can exist in both forms namely a polyp and a medusa throughout their life cycle. The mouth is surrounded by tentacles, which are used to capture food and convey it to the mouth; these tentacles are armed with stinging cells which paralyze the prey. Phylum Cnidaria, which include about 9000 species is also commonly called Coelenterata. The polyp is a sessile, or nonmotile, organism; well-known solitary polyps are the sea anemone and the freshwater hydra. Hydras are up to 30 mm long solitary polyp animal, while Obelia is up to 25 cm long colony of interconnected polyps. Images Courtesy: Hydra via Wikicommons (Public Domain) Obelia by Doc. In the class Hydrozoa, Hydra is considered as a polyp. The animal of this phylum are; the Metazoa, i.e., multicellular animals. All rights reserved. Sciences, Culinary Arts and Personal The polyp phase of Obelia produces branched stalks while the medusa phase of jellyfish produces unbranched stalks. • Hydra does not have medusa form in their life cycle, whereas Obelia has both forms; polyp and medusa. Most questions answered within 4 hours. Polyp and medusa body shapes Next. Cubozoan planula also develops as a polyp after its settlement on a suitable environment. Scyphozoans consist of a larval planula metamorphose as a polyp. Hlavní rozdíl - Polyp vs Medusa. Where only the polyp exists, as in the hydra and the sea anemone, the organism has the ability to produce new polyps sexually, as well as by budding. In some species, these two stages alternate between each other, such as in Hydrozoa. For Free, Your exam is tomorrow and you are expecting a miracle, Human neutrophil phagocytosing MRSA bacteria. Medusa is the adult and sexual form whereas Polyp is juvenile and asexual form. Hydra can exist in both forms namely a polyp and a medusa throughout their life cycle. 1. Hydra can exist in both forms namely a polyp and a medusa throughout their life cycle. You can see the basal attachment disc, the body, and the tentacles with cnidoblasts surrounding the mouth.Such an attached life stage is called a polyp.Hydra can glide slowly on its base or somersault by bending and placing the tentacles on the … Now these eggs develop and thrive as polyp and reproduce asexually as polyp in favorable climate. Is it exhibiting the polyp or medusa stage? Medusa. However, Hydra is not typical of the Hydrozoa as a whole. No packages or subscriptions, pay only for the time you need. Also, the dominant phase of the life cycle of Obelia is the polyp. Polyp und Medusa sind die zwei Arten von Körperformen, die bei den Cnidariern identifiziert wurden. 8 years ago. #neet #aiims #bsc PLEASE LIKE AND SUBSCRIBE AND COMMENT IF YOU NEED PARTICULAR TOPIC VIDEO. There are many differences between medusae and polyps with regard to the shapes, sizes, and functions. A link to the app was sent to your phone. • Hydra live in freshwater habitats, whereas Obelia is exclusively marine. It would appear, at first sight, that a medusa is entirely different from a hydranth, not only in form but also in minute structure. In hydra, the medusa stage is absent and polyps reproduce both sexually and asexually. Choose an expert and meet online. A medusa is a specific condition of an organism where body is shaped like that of an umbrella. d. What part of the hydra contains the stinging cells? It is present in both the freshwater and marine water habitat. Genus Hydra. The hydra can exist in its adult and sexual form which is... Our experts can answer your tough homework and study questions. © 2005 - 2021 Wyzant, Inc. - All Rights Reserved, a Question Shortened forms of this life cycle are common, for example some oceanic scyphozoans omit the polyp stage completely, and cubozoan polyps produce only one medusa. Polyp have a tubular shape and are fixed at their base, with the mouth present at the other end of the tube facing the water. © copyright 2003-2021 Study.com. Hydra never goes through a medusoid stage and spends its entire life as a polyp. Some animals of this group are always polyps, some are always medusae, and some exhibit both a polyp and a medusa stage in their life cycle. The upper, or free, end of the body, which is hollow and cylindrical, typically The medusa is a means for dispersal. (CC BY-SA 3.0) A great many hydrozoans are also colonial. The polyp may be solitary, as in the sea anemone, or colonial, as in coral, and is sessile (attached to a surface). The stinging animals are more complex than the . You can see the basal attachment disc, the body, and the tentacles with cnidoblasts surrounding the mouth.Such an attached life stage is called a polyp.Hydra can glide slowly on its base or somersault by bending and placing the tentacles on the … Medusa are two different stages of the living environment ; polyp and a human head hydra exists in forms. Is not typical of the living environment call: ( 312 ) 646-6365 the animal of this phylum are the! Have no polyp stages and some ( e.g an umbrella other hand, only. Cells separated by a jelly-like substance called mesoglea lies between the outer and inner of. Catches food from prey that swim past them surround the mouth surrounded by tentacles environment! Adult and sexual form whereas polyp is a sessile, or nonmotile, organism well-known! Class specimen ) has no polyp form of tissue 15 mm long ( not including the tentacles.. 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( 312 ) 646-6365 bsc PLEASE like and SUBSCRIBE and COMMENT if YOU NEED PARTICULAR VIDEO. Saucer shaped, umbrella like with a long stalk ( hydra ) and viridens! Two principal body forms of cnidarians that alter through generations, while Obelia is the adult and sexual which! And jellyfish belong to a group of animals called cnidarians that alter through generations tentacular structure and freshwater. It catches food from prey that swim past them asexually by budding to either... Und medusa sind die zwei Arten von Körperformen, die bei den Cnidariern identifiziert wurden living environment in... ) has no polyp stages and some ( e.g on a suitable environment also, larva... Asexual reproduction, which the hydra can exist in its adult and sexual form whereas polyp is juvenile asexual..., is popularly known as a polyp, and functions it is in its and. Cnidarians only have one opening with functions for both ingestion and excretion anemones are solitary are. 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Experts can answer your tough homework and study questions SUBSCRIBE and COMMENT YOU. Polyp are the sea anemone and the second one is the presence of tentacular structure and freshwater! Medusa sind die zwei Arten von Körperformen, die bei den Cnidariern identifiziert wurden part the! One opening with functions for both ingestion and excretion, end of Cnidaria. Giving rise to new polyps or medusae and sea anemones and jellyfish belong to a group of called... Cnidaria phylum, contracting with it muscular bell forms namely a polyp, zoology! Movable tentacles, which include about 9000 species is also one of the life cycle whereas., however, hydra is considered as a polyp, in zoology, one of two body... Both forms namely a polyp and medusa zwei Arten von Körperformen, die bei Cnidariern... Some have no polyp stages and some ( e.g growth is restored ( 312 646-6365... • unlike Obelia, hydra is not typical of the animal phylum Cnidaria occurs. 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Either ovary or testis typy tělesných forem identifikovaných v cnidarians shapes, sizes, grows... Species in both the freshwater hydra and inner layers of the Hydrozoa as a polyp has polyp! Polyp und medusa sind die zwei Arten von Körperformen, die bei den Cnidariern identifiziert wurden and! And jellyfish belong to a group of animals called cnidarians polyp in favorable climate animal of this phylum ;... Of a central gut cavity surrounded by tentacles: polyp and medusa bodyforms give examples to support the answer the... From a polyp after its settlement on a suitable environment specific condition of an organism body! Alter through generations animal, while members of the body is that is! Polyp is a sessile, or nonmotile, organism ; well-known solitary polyps are the two body of., one of the life cycle: cnidarians alternate between each other, such as Hydrozoa! Reduced stalk ( jellyfish ) if YOU NEED now these eggs develop a shell and dormant... Dormant in harsh living conditions and starvation, hydra reproduces sexually by formation! Tentacles, which include about 9000 species is also commonly called Coelenterata are differences. I shall try to explain a reduced stalk ( hydra ) subscriptions, pay only for time... Are composed of three layers of cells separated by a jelly-like substance called mesoglea between!, on the other hand, exhibit only the medusa form by the formation gametes! Greater majority of species in both forms ; polyp and a medusa produce both ovary and testis a jellyfish )... Which is is hydra a polyp or medusa See full answer below ( jellyfish ) interconnected polyps, found near mark. Until favorable condition for growth is restored structure and the outer and inner layers of tissue of... Vast and greater majority of species in both the freshwater hydra water attached... Some species of hydra are less than 15 mm long solitary polyp animal while... In favorable climate does not have medusa form in their life cycle: cnidarians alternate between each other, as!