CIRCULAROTY

• The function of the circulatory system is to transport gases, products of digestion, hormones, waste products, heat, water, and ions.
• The cardiovascular system consists of blood, blood vessels, heart, and lymphatic system.
• The cardiovascular system transports blood through blood vessels which include arteries, veins, capillaries, and heart chambers.
• The heart is supplied and drained by coronary vessels, has valves, and can contract either as a pacemaker (region of sinus venosus) or sino-atrial node.
• The heart consists of chambers such as the atrium, ventricle, and conus arteriosus (bulbus cordis).
• Hagfish lack major nerves innervating the heart to stimulate contraction, also known as the Branchial Heart.
• The lymphatic system consists of lymph, lymphatic vessels, lymphatic tissues, and includes the heart.
• Diverting blood to the systemic circuit can be beneficial as it increases the blood volume that can remove metabolites or gather oxygen stored in tissues.
• Diving turtles have depleted oxygen in their lungs and there is little advantage in circulating large quantities of blood to them.
• The flow of blood differs between the right and left sides of the heart in crocodiles.
• The basic vertebrate circulatory pattern includes the aortic arches, the portal systems, and the venous system.
• The sinus venosus is reduced and the conus arteriosus consists of three trunks in crocodiles.
• The hepatic portal transports absorbed end products of digestion to the liver.
• Efficient separation of oxygenated and deoxygenated bloodstreams is a characteristic of turtles, lizards, and snakes.
• There are three portal systems: the hepatic portal, the splenic portal, and the superior mesenteric portal.
• Aortic arches are unpaired branches of the aorta that supply the viscera.
• The sinus venosus is reduced and the conus arteriosus consists of two trunks in humans.
• Hagfish lack cardiac muscles, atrial contraction assists ventricular filling, and the heart is single atrium partially divided.
• In Hagfish, blood can be diverted through shunts to equalize and distribute temporary pressure fluctuations, heat distribution, and allocate blood to active organs.
• In fishes, the circulatory system functions through the progressive displacement of inflow structures from caudal to dorsal (fishes) & cephalad (reptiles) position.
• In amphibians, reptiles, birds, and mammals, the thymus is located in the first branchial arch.
• In amphibians, reptiles, birds, and mammals, the bone marrow is located in the central part of the body.
• Tonsils are present in amphibians, reptiles, birds, and mammals.
• Amphibia, reptiles, birds, and mammals have a thymus.
• Pulse waves traveling within adjacent arterial walls
• In mammals, the thymus, bone marrow, and spleen are important organs.
• In amphibians, reptiles, birds, and mammals, the Peyer's patches and the vermiform appendix are part of the digestive system.
• Birds have a spleen.
• Tonsils are present in Crole and Soley (2012) mammals.
• The cisterna chyli is a sac at the lower end of the thoracic duct into which lymph from the intestinal trunk and two lumbar lymphatic trunks flow in amphibians, reptiles, birds, and mammals.
• Birds have a Bursa of Fabricius, a pouch in the cloaca containing lymphatic tissue.
• Peyer's patches and the vermiform appendix are part of the mammalian digestive system.
• The thymus is an important organ in birds.
• The cisterna chyli is a sac at the lower end of the thoracic duct into which lymph from the intestinal trunk and two lumbar lymphatic trunks flow.
• Lymph nodes are present in water birds.
• Lymph nodes are present in amphibians, reptiles, birds, and mammals.
• In amphibians, reptiles, birds, and mammals, the spleen is located in the upper part of the abdomen.
• Abdominal Veins: Abdominal Veins are absent in humans.
• Renal Portal: direct route for delivering metabolic by-products from active locomotion involving the caudal musculature; recovery of water & important solutes.
• Chondrictyes & primitive fishes lack a true lymphatic system (hemolymphatic system), while Amphibians have lymph sacs and Reptiles have lymph hearts.