Search results
Results From The WOW.Com Content Network
In cnidarians, the gastrovascular system is also known as the coelenteron, and is commonly known as a "blind gut" or "blind sac", since food enters and waste exits through the same orifice. The radially symmetrical cnidarians have a sac-like body in two distinct layers, the epidermis and gastrodermis , with a jellylike layer called the mesoglea ...
Pacific sea nettles, Chrysaora fuscescens. Cnidaria (/ n ɪ ˈ d ɛər i ə, n aɪ-/ nih-DAIR-ee-ə, NY-) [4] is a phylum under kingdom Animalia containing over 11,000 species [5] of aquatic invertebrates found both in fresh water and marine environments (predominantly the latter), including jellyfish, hydroids, sea anemones, corals and some of the smallest marine parasites.
Coelenterata is a term encompassing the animal phyla Cnidaria (corals, true jellies, sea anemones, sea pens, and their relatives) and Ctenophora (comb jellies). The name comes from Ancient Greek κοῖλος (koîlos) 'hollow' and ἔντερον (énteron) 'intestine', referring to the hollow body cavity common to these two phyla.
The water vascular system is a hydraulic system used by echinoderms, such as sea stars and sea urchins, for locomotion, food and waste transportation, and respiration. [1] The system is composed of canals connecting numerous tube feet. Echinoderms move by alternately contracting muscles that force water into the tube feet, causing them to ...
a Beroe ovata, b unidentified cydippid, c "Tortugas red" cydippid, d Bathocyroe fosteri, e Mnemiopsis leidyi, and f Ocyropsis sp. [17]. Among animal phyla, the ctenophores are more complex than sponges, about as complex as cnidarians (jellyfish, sea anemones, etc.), and less complex than bilaterians (which include almost all other animals).
The nervous system present is primitive, consisting of a simple net composed of naked and largely non-polar neurons. In addition P. noctiluca also lacks a gaseous exchange, excretory and circulatory system. However cnidaria have evolved cnidae, cells which serve for a variety of functions that include prey capture, defense, locomotion and ...
Melo amphora moving across coral at low tide. In some (but not all) sea snails, marine gastropod molluscs, the animal has an anterior extension of the mantle called a siphon, or inhalant siphon, through which water is drawn into the mantle cavity and over the gill for respiration.
In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. [1] [2] It includes the cardiovascular system, or vascular system, that consists of the heart and blood vessels (from Greek kardia meaning heart, and Latin vascula meaning vessels).