What is the function of hydranths?
What is the function of hydranths?
The hydranths are more numerous and constitute the feeding zooids. Each of them resembles a Hydra in appearance, having about twenty solid tentacles. A hydranth, is encased and protected in a transparent vase-like hydro-theca. It captures minute prey by using its tentacles which contain batteries of nematocysts.
What is Hydranth polyp?
hydranth. / (ˈhaɪdrænθ) / noun. a polyp in a colony of hydrozoan coelenterates that is specialized for feeding rather than reproduction.
What does a Gonangium do?
a reproductive polyp of a colonial hydroid, giving rise asexually to medusa buds.
What is hydrocaulus?
hydrocaulus (plural hydrocauli) (zoology) The hollow stem of a hydroid, either simple or branched.
What is Medusa and Blastostyle?
The blastostyles are the reproductive zooids as they reproduce asexually to give rise to numerous lateral buds called medusa buds or gonophores. These buds develop into third type of zooids of the colony called medusae. Medusae: These are small, transparent, solitary, free swimming saucer-shaped or bell-shaped zooids.
Are polyps benign?
Polyps are benign (non-cancerous) growths, but cancer can start in some types of polyps. These polyps can be thought of as pre-cancers, which is why it is important to have them removed.
What is Blastostyle in obelia?
The blastostyles are the reproductive zooids as they reproduce asexually to give rise to numerous lateral buds called medusa buds or gonophores. These buds develop into third type of zooids of the colony called medusae.
How do polyps produce medusa?
Complete answer: By budding Polyp forms the medusa while the medusa by sexual reproduction forms polyps. A medusa produces gametes (male & females), which are shed into the water; upon fertilization, the structure develops into a swimming larva, which later on settles and develops in a polyp.
What is the Gonangium?
Gonagium: reproductive polyps. Tentacles. Hypostome. Medusa Buds: seen within the gonania; become free-swimming medusae.
What is Monostichodont?
In leeches, having only one row of teeth in each jaw.
What do you mean by Hypostome?
: any of several structures associated with the mouth: such as. a : the manubrium of a hydrozoan. b : a rodlike organ that arises at the base of the beak in various mites and ticks.
Which is the best definition of a hydranth?
Definition of hydranth. : one of the feeding zooids of a hydroid colony.
What kind of buds are on a hydranth?
As a general rule polyp-buds are produced from the hydrorhiza and hydrocaulus, while medusa-buds are formed on the hydranth. Hydranth more shortened, daisy-like in form, with two whorls of tentacles, oral and aboral.
What kind of hydranth has no tentacles?
Speaking generally, three principal types of hydranth can be distinguished, each with subordinate varieties of form. Hydranth with tentacles reduced below four; type of Lar (fig. 11), Monobrachium, &c. In both cases the hydranth is extremely reduced and has no tentacles, and the polyp forms a colony by budding from the base.
Who was the first person to use the word hydranth?
Note: The word was probably introduced by the Irish-born biologist George James Allman (1812-98) in A Monograph of the Gymnoblastic or Tubularian Hydroids (London, 1871), p. xiv. Test your knowledge – and maybe learn something along the way.