“Cnidarians” is Greek for “stinging nettle” (“Introduction to Cnidaria"). Phylum Cnidaria include freshwater hydra, jellyfish, and corals. Each of these invertebrates go through transitions in body forms. Jellyfish are the most unusual and complex out of the phylum. Jellyfish are in the class Scyphozoa, which means true jellyfish.
Cnidarians are found in the Mediterranean and in the oceans. They can live in the ocean as well as coastal waters. But the primary habitat for Cnidarians are in the open ocean. Jellyfish can live in any oceans. There are deep water and shallow water jellyfish. Certain jellyfish, such as the Pelagia Noctiluca, can live anywhere that the ocean currents decide to carry it ("Phyla Cnidaria, Platyhelminthes, and Nematoda").
A jellyfish’s unique body structure helps it move, feed, and protect itself. Their body is known as the bell. During the bell stage, medusa, the jellyfish is mobile and is specialized for swimming. But in some Cnidarians, the bell stage only occurs in the embryo stage ("Phyla Cnidaria, Platyhelminthes, and Nematoda"). The medusa then produces an egg, which grows into a polyp (vase stage) which is sessile (or immobile) life. Jellyfish do not have a back or front, left or right. They don’t have a heart, head, legs, or fins (Zimmer). They have a stomach pouch to hold food, the bell (body), oral arms which bring the captured food to the mouth, tentacles which sting and kill prey, a mouth connected to digestive structures to digest food, and gonads which are reproductive organs. Jellyfish are also 95% water (Northeaster University).
Jellyfish move by expanding and contracting to push the water behind them. In between each contraction and expansion is a pause so that a vortex can be created ...
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... The jellyfish don’t have an excretory system, so the hole for the mouth serves as an anus as well (“Pelagia Noctiluca”).
A jellyfish doesn’t have a circulatory system because it is radially symmetrical, meaning they have a symmetrical arrangement of parts about a central point. (“Pelagia Noctiluca”)
Jellyfish are a unique and interesting species. Even though jellyfish look complex they are simple. They have very little internal systems, such as respiratory, circulatory, excretory, and nervous systems. Even though they don’t have a nervous system they have the ability to sting and kill prey to survive. Chemicals can cause them to glow. They can move by expansions and contractions. They can reproduce both asexually and sexually. They are simple invertebrates but yet are still unique and interesting. Jellyfish are fascinating and more complex than they appear to be.
Organized in the class Actinopterygii, seahorses, Hippocampus spp., are marine dwelling organisms found in bodies of water which span from tropical to temperate zones around the Earth. As cited by Foster in Life History and Ecology of Seahorses, research by R. A. Fritschze suggests that the genus Hippocampus diverged at least 20 million years ago from its ancestral origins. Research pertaining to organisms organized under the genus Hippocampus are conflicting in regards to the number species contained within it, although a general figure places the number at around fifty discovered species(website source). These odd-looking organisms reside at shallow depths of less than 30 meters and can be found in habitats containing seagrass beds and coral reefs(Foster 10). Hippocampus spp. are all predatory organisms, their main sources of food consist of small crustaceans and fish, as well as other organisms which are small enough to be consumed(lourie 10). Although Hippocampus spp. are predatory, their size and restricted mobility capabilities place them at risk of being prey for other carnivorous organisms.
Imagine a creature that has a skeleton on the outside of its body, that has eyes that protrude on stalks, and whose blood doesn't flow through blood vessels but, instead, pools and surrounds body tissues. What is this monstrous creature? What if I were to tell you this isn't a monster, but something you've probably seen and maybe even eaten?! Yep, this strange creature is a __crustacean__! There are over 50,000 species of crustacean and they come in all shapes and sizes, from an ocean-dwelling crab to an immobile barnacle! But before we delve into the types of crustaceans, let's take a moment to go over the characteristics and anatomy they share.
Vince, Gaia. "Jellyfish Blooms Creating Oceans of Slime." BBC.com. British Broadcasting Company, 5 Apr. 2012. Web. 1 May 2012.
They are invertebrates (spineless animals) and are cousins of anemones and jellyfish. When thousands of these animals are grouped together, they are referred to as coral colonies. Each coral "tree" or "mound" is one colony of coral polyps. A polyp has a sac-like body and an opening or mouth encircled by stinging tentacles called cnidae.
The Portuguese Man of War, also known as Physalia physalis, is often found in warm waters of the tropics, subtropics and Gulf Stream and is armed with thick nematocysts that can reach up to 165 feet. The Portuguese Man of War has a translucent blue, pink gas filled body that reaches lengths up to 12 inches long. The poisonous creature got its name, because of its appearance to looking like the sail of a Portuguese battleship. The sting of a Portuguese Man of War if very painful, but not deadly. The pain is to be described as putting hot charcoal on your flesh. The pain of the nematocysts can last for hours and can cause welts and red marks to cover the areas the tentacles had touched. There are also symptoms of nausea and difficulty breathing. This particular jellyfish is not considered a “true” jellyfish. In fact, The Portuguese Man of War consists of modified feeding polyps and a reproductive medusa called a float. Since the jellyfish is not a fast moving carnivore the diet of a Portuguese Man of War consists of eating small fish or other creatures it can get ahold of. The nematocysts will paralyze the prey which then will be consumed by the jellyfish. Because jellyfish are venomous most marine animals cannot eat them but there are a few exceptions. For example, sea turtles love to eat the Portuguese Man of War. Other jellyfish are preyed upon by spadefish, sunfish, and loggerheaded
On every continent we find fossils of sea creatures in rock layers that today are high above sea level. For example, most of the rock layers in the walls of the Grand Canyon contain marine fossils. This includes the Kaibab Limestone at the top of the strata sequence and exposed at the rim of the canyon, which today is 7,000–8,000 feet above sea level.2 This limestone was therefore deposited beneath lime sediment-charged ocean waters, which swept over northern Arizona (and beyond). Other rock layers of the Grand Canyon also contain large numbers of marine fossils. The best example is the Redwall Limestone, which commonly contains fossil brachiopods (a type of clam), corals, bryozoans (lace corals), crinoids (sea-lilies), bivalves (other types
Through a process called genome sequencing the scientist were able to deduct that myxozoans, are actually degenerated cnidarians. Myxozoans are a parasite that infects marine creatures. The cnidarians phylum also includes jellyfish, corals and sea anemones.
The body of the shrimp is two parts the thorax which is the body and the head , the body pieces are connected by the cephalorax and a narrow abdomen. The mouth if the shrimp works with the gills so they can be used. Shrimp have a hard shell that keeps everything together and protects them, its legs, eyes, and rostrum grow out of the hard shell. The use their nose or a sharp peak which there there basically the sing thing to protect their self from all the bigger and other animals it come in contact with and it sticks them with and it has a length that the shrimp lets out to be able to reach where the shrimp wants to get the other animals. Shrimp have some similarities to fish like when they travel, breed, and eat its usually done in schools (schools area group of the species). A (shrimp) single female is capable of producing a large number of offspring, one shrimp can lay up to one million eggs in a single session, take two weeks to hatch it takes two weeks to
Soft corals are grouped in the phylum Cnidaria, class Anthozoa, and order Alcyonacea. Their distinguishing characteristic is that their polyps always bear eight tentacles which are on both edges fringed by rows of pinnules (Fabricius and De’ath, 2002). The common name “soft coral” comes from the fact that they have no massive external skeleton as compared to the more commonly studied hard corals.
They have a wide mouth and broad spiny head and venom glands that may occur at the base of fin spines which can produce deep and painful wounds. The feathery fins which cover the scorpion fish body help in the camouflaging of the animals into the surrounding coral. Also, the coral- like frilly, fleshy flaps of skin protruding from its chin add
Piatigorsky, Z., Kozmik. 2004.Cubozoan jellyfish: an Evo/Devo model for eyes and other sensory systems. Int J Dev Biol 48: 719–729
First of all, an octopus is a cellapod. Which means it has a soft body, and no bones. An octopus also has eight arms, large useful eyes, and suction cups. ( Octopuses and Squid, page 6 by: Tori Miller.) All of these traits are mostly used for hunting. Eight arms come in handy when your prey is fast and can get away easily, large eyes are useful when you need to see in the dark or the depths of the ocean, and suction cups are used when they need to grab hold of something.( Octopuses Squid, page 14.) ( National Geographic, Octopus Facts.) Octopuses have blue blood caused by copper and bag like bodies. When born they're 1/4 of an inch and don't rely on...
A fish heart is one of the simplest vertebrate hearts. The circulatory system is a single circulation, with a two-chambered heart. The blood from the fish’s atrium is pumped into the ventricle. Blood is pumped to the gills from the ventricle where gas exchange occurs in the gill filaments. This is called gills circulation. The carbon dioxide is removed while the oxygen is taken in. This re-oxygenated blood is then transport to the rest of the body’s tissues and organs to get rid of carbon dioxide and exchanging it with life-giving oxygen. This circulation is called systemic circulation. Blood is eventually pumped back into the heart’s atrium chamber where the circulation begins again. This unidirectional flow of blood creates a gradient of
Dinoflagellates have a pair of flagellum, transverse flagellum, that are wound up around the body and then when whipped in a wavelike fashion causes the cell to go in a spinning motion, giving it a forward propulsion. This helps the dinoflagellates keep their planktonic existence because it can help them stay at the top of the water column, making it easier for them to perform