How do you identify Scyphozoa?
Scyphozoans share a number of attributes with other cnidarians: (1) they typically possess tentacles, (2) their symmetry is radial, (3) the body wall consists of an outer epidermis and inner gastrodermis, separated by a layer of jelly-like mesoglea, (4) the mouth is the only opening to the digestive system, (5) …
What are two characteristics of the class Scyphozoa?
Scyphozoans exhibit the main characteristics of cnidarians. They have radial symmetry and are diploblastic, meaning that their body wall consists of the outer epidermis (ectoderm) and the inner gastrodermis (endoderm), which are separated by mesoglea. They have nematocysts, which are characteristic of the phylum.
What is the difference between Hydrozoa and Scyphozoa?
The difference between most hydrozoans and most scyphozoans is that in hydrozoans, the polyp stage usually predominates, with the medusa small or sometimes absent. Hydrozoans also lack cells in the mesoglea, the jelly layer found between the basic cell layers, whereas scyphozoans contain amoeboid cells in the mesoglea.
What are the main life stages of Scyphozoa?
1: Lifecycle of a jellyfish: The lifecycle of a jellyfish includes two stages: the medusa stage and the polyp stage. The polyp reproduces asexually by budding,while the medusa reproduces sexually.
How do Scyphozoa move?
Medusae move by pulsating muscular contractions of the bell, which is supported by a thick gelatinous and fibrous mesogloea. Only weak swimmers, scyphozoans are carried great distances in the plankton by the seas’ currents.
What animals belong to Scyphozoa?
The class Scyphozoa can be found in the phylum of Cnidaria, the phylum of the “stinging” creatures, such as jellyfish. There are approximately 200 species that belong to the class Scyphozoa, and they are the most familiar of the gelatinous creatures of our world. These include, sea nettles, moon jellies and jellyfish.
What is the function of Gastrodermis?
The gastrodermis is the inner layer of cells that serves as a lining membrane of the gastrovascular cavity of Cnidarians. The term is also used for the analogous inner epithelial layer of Ctenophores. It has been shown that the gastrodermis is among the sites where early signals of heat stress are expressed in corals.
What animals belong to hydrozoa?
Some examples of hydrozoans are the freshwater jelly (Craspedacusta sowerbyi), freshwater polyps (Hydra), Obelia, Portuguese man o’ war (Physalia physalis), chondrophores (Porpitidae), “air fern” (Sertularia argentea), and pink-hearted hydroids (Tubularia).
What is the function of the Gastrovascular cavity?
The gastrovascular cavity is the primary organ of digestion and circulation in two major animal phyla: the Coelenterates or cnidarians (including jellyfish and corals) and Platyhelminthes (flatworms). The cavity may be extensively branched into a system of canals.
What is the order of Scyphozoa?
The four orders are Stauromedusae, the stalked jellyfish; Coronatae, the crown or grooved jellyfish; Semaeostomeae; and Rhizostomeae.
How do Scyphozoa breath?
Like the other cnidaria, scyphozoans have no head and no special organs for respiration or excretion.
What kind of structure does a Scyphozoa have?
Scyphozoans usually display a four-part symmetry and have an internal gelatinous material called mesoglea, which provides the same structural integrity as a skeleton. The mesoglea includes mobile amoeboid cells originating from the epidermis.
Where did the name Scyphozoa come from and why?
It may include the extinct fossil group the Conulariida, whose affinities are uncertain and widely debated. The class name Scyphozoa comes from the Greek word skyphos (σκύφος), denoting a kind of drinking cup and alluding to the cup shape of the organism. Scyphozoans have existed from the earliest Cambrian to the present.
Which is the best description of the anatomy of the foot?
Anatomy of the foot 1 Calcaneus (heel bone) 2 Talus (ankle bone) 3 Transverse tarsal joint 4 Navicular bone 5 Lateral cuneiform bone 6 Intermediate cuneiform bone 7 Medial cuneiform bone 8 Metatarsal bones 9 Proximal phalanges 10 Distal phalanges 11 Tarsometatarsal joint 12 Cuboid More
Where are the eyespots located in a scyphozoan?
Scyphozoan polyps and medusae exhibit no cephalization and contain no brain, but in some species, light-sensitive eyespots are located along the bell margin of the medusa. Scyphozoan medusae differ from those of hydrozoans in lacking a velum.