What is a polyp and medusa stage?
What is a polyp and medusa stage?
Polyp is a sessile life cycle stage of the Cnidaria phylum. Medusa is a mobile life cycle stage of the Cnidaria phylum, contracting with it muscular bell. 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.
Do cnidarians have nematocysts?
Nematocysts or cnidocysts represent the common feature of all cnidarians. They are large organelles produced from the Golgi apparatus as a secretory product within a specialized cell, the nematocyte or cnidocyte. Nematocysts are predominantly used for prey capture and defense, but also for locomotion.
Do cnidarians have a polyp stages?
They have two different morphologies: a polyp stage and a medusa stage (not all classes will have both through out their life time). Both stages have radial symmetry. The polyp stage tends to be sessile and the medusa stage is mobile. Some species of Cnidarians have bioluminescence.
Do all cnidarians have a polyp and medusa stage?
Cnidarians have two body forms—polyp and medusa—which often occur within the life cycle of a single cnidarian. Sea nettle (Chrysaora fuscescens). Thus, the polyp is essentially a juvenile form, while the medusa is the adult form. In contrast, anthozoans are polypoid cnidarians and do not have a medusa stage.
What are polyps and medusa in Cnidaria?
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 a polyp in cnidarians?
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.
Do cnidarians have a Coelom?
A coelom is a fully-encased, fluid-filled body cavity (gut) lined with mesodermic tissue. Cnidarians are not considered to have a coelom because they are diploblastic, so they don’t have any mesodermic tissue. Cnidaria are a phylum consisting of aquatic animals like jellyfish, anemones, and corals.
Which cnidarians exhibit only polyp stage?
Members of one class of cnidarians, the Anthozoa, exhibit only the polyp body form; most species of the other three classes (hydrozoans, scyphozoans, and cubozoans) alternate in their life cycles between polypoid and medusoid (free-swimming) body forms.
Which organism possesses both a polyp and medusa phase of life?
Jellyfish have two different body forms – the medusa and the polyp. During the polyp form, jellyfish can reproduce asexually by a process called budding.
What is polyp in Cnidaria?
What are the polyp and medusa forms of cnidarians?
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. Consequently, how are polyp and medusa forms of cnidarians similar and different?
Is the medusa stage the same as the polyp stage?
The phylum Cnidaria includes species existing only in the polyp stage (Anthozoa), species existing in the medusa stage, and species with both life cycle stages (Hydrozoa).
What kind of organisms are in the polyp stage?
The phylum Cnidaria includes species existing only in the polyp stage (Anthozoa), species existing in the medusa stage, and species with both life cycle stages (Hydrozoa). Corals, sea anemones, jellyfish, and hydroids are cnidarians. What is Polyp? Polyp is a sessile life cycle stage of the species belonging to the Cnidaria phylum.
What kind of body shape does a cnidarian have?
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.
