The Phylum Arthropoda
Brief Overview
The phylum arthropoda is the largest phylum in the animal kingdom, as about 84% of all known animal species are a member of this phylum. Arthropods are represented in every enviornment on earth, including aquatic and terrestial enviornments, and adjust very well. About 1 million species of arthropods have been named, most of which are insects. A distinguished feature of arthropods is the presence of a joined skeleton composed of complex sugar, named chitin, and binded to protein. The circulatory system of all arthropods is open, as it contains a heart, and a system of arteries. The heart delivers blood into tissue spaces, or hemocoels, where it eventually drains back into a large sinus surrounding the heart. When the heart is contracting, closed valves prohibit the blood from flowing back and force it into the arteries of the tissues, where it is forced to flow to other hemocoels. The circulatory system of Arthropods is similar to that of Molluscs, as both systems are open, despite the fact that Molluscs are made up of invertebrates, while Arthropods are made up of vertebrates. However, arthropods are more evolved due to its backbone, and its greater development of tissue around the circulatory system.
The phylum arthropoda is the largest phylum in the animal kingdom, as about 84% of all known animal species are a member of this phylum. Arthropods are represented in every enviornment on earth, including aquatic and terrestial enviornments, and adjust very well. About 1 million species of arthropods have been named, most of which are insects. A distinguished feature of arthropods is the presence of a joined skeleton composed of complex sugar, named chitin, and binded to protein. The circulatory system of all arthropods is open, as it contains a heart, and a system of arteries. The heart delivers blood into tissue spaces, or hemocoels, where it eventually drains back into a large sinus surrounding the heart. When the heart is contracting, closed valves prohibit the blood from flowing back and force it into the arteries of the tissues, where it is forced to flow to other hemocoels. The circulatory system of Arthropods is similar to that of Molluscs, as both systems are open, despite the fact that Molluscs are made up of invertebrates, while Arthropods are made up of vertebrates. However, arthropods are more evolved due to its backbone, and its greater development of tissue around the circulatory system.
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Artemia salina (Brine Shrimp)
Like most arthropods, Artemia salina have an open circulatory system, and has a heart and arteries. However, along with this, Artemia salina also has gills within a very well developed circulatory system. Along with these gills, Artemia salina also has accessory hearts to increase blood flow through the gills.
Like most arthropods, Artemia salina have an open circulatory system, and has a heart and arteries. However, along with this, Artemia salina also has gills within a very well developed circulatory system. Along with these gills, Artemia salina also has accessory hearts to increase blood flow through the gills.
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Limulus polyphemus (Horseshoe Crab)
Limulus polyphemus, like other arthropods, has an open circulatory system which includes a heart and arteries. Along with this, the Limulus polyphemus has a series of book gills, or gills arranged in folds) on either side of its body along its circulatory pathway. Blood passes through these from the ventral sinus for oxygenation prior to its return to the heart.
Limulus polyphemus, like other arthropods, has an open circulatory system which includes a heart and arteries. Along with this, the Limulus polyphemus has a series of book gills, or gills arranged in folds) on either side of its body along its circulatory pathway. Blood passes through these from the ventral sinus for oxygenation prior to its return to the heart.
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Araneus diadematus (Spider)
Araneus diadematus shares with most other arthropods a heart and arteries in its open circulatory system. In addition to this, Araneus diadematus also contains book gills along its circulatory pathway, similar to that of Limulus polyphemus, as well as reduced tracheal and vascular systems. This causes blood circulation when the muscles of the body contract. Also, the Araneus diadematus has a high blood pressure, which is maintained by valves in the aorta.
Araneus diadematus shares with most other arthropods a heart and arteries in its open circulatory system. In addition to this, Araneus diadematus also contains book gills along its circulatory pathway, similar to that of Limulus polyphemus, as well as reduced tracheal and vascular systems. This causes blood circulation when the muscles of the body contract. Also, the Araneus diadematus has a high blood pressure, which is maintained by valves in the aorta.