hemocoel
Quick Summary
A hemocoel is a body cavity found in some invertebrates, such as arthropods and certain mollusks. This cavity contains blood or hemolymph and functions as a part of the circulatory system. The term "hemocoelom" can also refer to the part of the embryonic coelom where the heart develops, or it can be used synonymously with hemocoel. In contrast, animals like acornworms have an open vascular system with contractile vessels and sinus channels, where blood circulates. Echinoderms, like sea urchins and starfishes, have complex systems involving coelomic fluid, a reduced blood-vascular system of sinuses, and a water vascular system. Spoonworms (Echiura) possess a circulatory system with main dorsal and ventral vessels, and coelomic fluid may assist in oxygen transport.12345
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arthropodCirculatory system…blood into tissue spaces (hemocoels), from which it eventually drains back to a large pericardial sinus surrounding the heart. A varying number of paired openings (ostia) are located along the length of the heart and permit blood to flow in when the valves are open. When the heart is…
Read More…blood into tissue spaces (hemocoels), from which it eventually drains back to a large pericardial sinus surrounding the heart. A varying number of paired openings (ostia) are located along the length of the heart and permit blood to flow in when the valves are open. When the heart is…
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skeletonSkeletomusculature of arthropods…hydrostatic skeleton formed by the hemocoele, or enlarged blood-filled spaces. The cuticle may be flexible or stiff, but it does not stretch. In the Onychophora (e.g., Peripatus) the cuticle is thin and much-folded, thus allowing great changes in the body shape. The muscular body wall, as in annelids, works against…
Read More…hydrostatic skeleton formed by the hemocoele, or enlarged blood-filled spaces. The cuticle may be flexible or stiff, but it does not stretch. In the Onychophora (e.g., Peripatus) the cuticle is thin and much-folded, thus allowing great changes in the body shape. The muscular body wall, as in annelids, works against…
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lobopod…to the formation of a hemocoel; it may also have permitted the development of a firmer cuticle, leading to the evolution of molting. The development of the cuticle also led to the loss of external cilia.
Read More…to the formation of a hemocoel; it may also have permitted the development of a firmer cuticle, leading to the evolution of molting. The development of the cuticle also led to the loss of external cilia.
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molluskMuscles and tissues…tissue or fluid-filled spaces (hemocoel), or both. When filled with fluid, the hemocoel expands against the body wall and fibrous tissues, providing a rigid framework and stretching opposing muscles. This same fluid pressure, generated by contraction of other muscles, allows the foot to extend from the shell and penetrate…
Read More…tissue or fluid-filled spaces (hemocoel), or both. When filled with fluid, the hemocoel expands against the body wall and fibrous tissues, providing a rigid framework and stretching opposing muscles. This same fluid pressure, generated by contraction of other muscles, allows the foot to extend from the shell and penetrate…
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tardigrade…the tardigrade’s body cavity (hemocoel) is filled with fluid that transports blood and oxygen (the latter of which diffuses through the animal’s integument and is stored in cells within the hemocoel). The alimentary canal traverses the body from end to end. Most plant-eating tardigrades feed by piercing individual plant…
Read More…the tardigrade’s body cavity (hemocoel) is filled with fluid that transports blood and oxygen (the latter of which diffuses through the animal’s integument and is stored in cells within the hemocoel). The alimentary canal traverses the body from end to end. Most plant-eating tardigrades feed by piercing individual plant…
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