Planula, plural planulae, free-swimming or crawling larval type common in many species of the phylum Cnidaria (e.g., jellyfish, corals, and sea anemones). The planula body is more or less cylindrical or egg-shaped and bears numerous cilia (tiny hairlike projections), which are used for locomotion.
What is planula larva in biology?
A planula is the free-swimming, flattened, ciliated, bilaterally symmetric larval form of various cnidarian species and also in some species of Ctenophores. Some groups of Nemerteans also produce larvae that are very similar to the planula.
What does a planula become?
These fuse to form a free-floating larval stage, a planula, which settles and metamorphoses into a new polyp . The phylum is also characterized by the presence of stinging cells for the capture of prey (nematocysts), which are particularly abundant in the tentacles and which give the phylum its name.
What is planula stage?
The planula is the first larval stage of Aurelia , and is formed soon after the egg and sperm combine to form a zygote. The planula is lined with cilia and eventually settles, forming a scyphistoma. Planula larval stages are common to many Cnidarians.
What is a polyp animal?
Polyp, in zoology, one of two principal body forms occurring in members of the animal phylum Cnidaria . The polyp may be solitary, as in the sea anemone, or colonial, as in coral, and is sessile (attached to a surface). ... The lower end of the polyp typically is adapted for attachment to a surface.
What is a jellyfish planula?
Planula, plural planulae, free-swimming or crawling larval type common in many species of the phylum Cnidaria (e.g., jellyfish, corals, and sea anemones). ... Planulae are produced by the polyp form in sea anemones and other anthozoans and by the medusa form in most other cnidarians.
What is ror2 planula?
So, what does the Planula do exactly? ... The Planula allows the player to receive flat healing when attacked , according to the Risk of Rain 2 wiki the Planula will “Heal from incoming damage for 15 (+15 per stack)”.
What is the difference between planula and Amphiblastula?
Complete answer:
Planula is the ciliated, bilaterally symmetrical, flattened, free swimming larva of organisms in the phylum Cnidaria. ... Amphiblastula is the free swimming larva of certain sponges. Obelia is not a sponge.
How does an adult hydra attach to feed?
explain how the adult hydra attaches to feed? the adult hydra have a sticky material that they used t attach to surfaces .
How do jellyfish reproduce?
Throughout their lifecycle, jellyfish take on two different body forms: medusa and polyps. Polyps can reproduce asexually by budding , while medusae spawn eggs and sperm to reproduce sexually.
How quickly do jellyfish reproduce?
At the polyp stage, jellies resemble tiny anemones and reproduce asexually by strobilation. When a polyp strobilates—segmenting its body to reproduce—it releases tiny ephyra into the water. Within a few weeks , a bell appears and the ephyra are considered medusa, starting the whole process over again!
What eats a jellyfish?
The main predator of jellyfish is other jellyfish, usually of a different species. But jellyfish also have a number of other natural enemies that like to eat them. These predators include tunas , sharks, swordfish and some species of salmon. Sea turtles also like to eat jellyfish.
What is the lifespan of a jellyfish?
Most jellyfish are short lived. Medusa or adult jellyfish typically live for a few months , depending on the species, although some species can live for 2-3 years in captivity. Polyps can live and reproduce asexually for several years, or even decades. One jellyfish species is almost immortal.
Is coral a plant or animal?
Though coral may look like a colorful plant growing from roots in the seafloor, it is actually an animal . Corals are known as colonial organisms, because many individual creatures live and grow while connected to each other. They are also dependent on one another for survival.
What is the function of polyps?
Polyps extend their tentacles, particularly at night, containing coiled stinging nettle-like cells or nematocysts which pierce and poison and firmly hold living prey paralysing or killing them .
Do polyps turn into 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.
