How does the circulatory system of a frog differ from that of a human?
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humans (mammals) have 4 chambered hearts and frogs (amphibians) have three chambered hearts.\nin humans, half the heart sends oxygen poor blood to the lungs and the other half sends oxygen rich blood to the body. each half has its own atrium that collects blood, and ventricle that pumps it.\nin frogs, there are seperate atriums but 1 ventricle that pumps both at the same time, so the low oxygen and high oxygen blood mix a little bit.
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Question is a little vague......anatomy is structural and function is physiological, so I am not sure what your question really is; is it about anatomy or physiology or both? So RSVP:  Are you asking about the unique physiology or anatomy of amphibians?\n\nThey have many structures in common with the other tetrapod vertebrates, but also have unique structures as amphibians.  Plus each sub-class-type of amphibian (frogs-toads) vs (newts-salamanders) vs caecilians are each different.\n\nAll amphibians have their unique slimey scaleless skin through which they attain most of their oxygen and release their CO2 by diffusion, their 3-chambered heart with 2 atria and 1 ventricle, their external fertilization type reproductive system that has egg-larva-tadpole and adult.  Their respiratory system changes at each stage of development. As tadpoles they use their gills. As they metamorphose to adults,the gills are absorbed and lungs develop to breathe air although they lack a diaphragm and ribs (in most...some amphibians retain larval stage for their whole life...axolotyl). They have kidneys and bladder for excretory system; endoskeleton is bone and has most of the same bones as us, although some are fused (radio-ulna, fibulo-tibia; no skull protecting brain, unusual urostyle bone of pelvis.
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frogs like to swim in the water and are more aquatic than terrestrial, but they have very well developed meaty leg muscles, (both the calf and the thighs) and many muscles the same as humans which they can use for hopping too. They just use their hind legs for hopping though.  Those puny little arms-hands-muscles are not used for much other than propping themselves up when sitting, or a male may squeeze a female when he is on her back mating with her.
395359
oxygen molecule in lungs diffuses into the blood stream return to the heart via the pulmonary vein (the only vein to carry oxygenated blood) into the left atrium, left ventricle, through the aortic semilunar valve, through the ascending aorta, arch of the aorta, descending aorta, common illiac artery, external illiac artery, femoral artery... from there it  depends where in the hind leg... by the way these are human names, I don't know how many would be different for animals... my comparative anatomy teacher used to make us do these kinds of questions all the time ;-)
64374
The above answer is correct, but the cardiovascular system is not just the heart. That's the "cardio", but the "vascular" part is all of the arteries, veins, and capillaries that distribute the blood throughout the body.\nThe respiratory system does indeed oxygenate the blood, but is also responsible for eliminating carbon dioxide from the body as well. As the body uses oxygen for metabolism, it produces carbon dioxide. If this is not eliminated from the body fairly quickly, it builds up, and without going into alot of detail, you die.
348835
Humans have a closed circulatory system.  It is when the blood is contain in the veins and arteries.  Where the arteries take blood to the body and the veins take it directly back.  In an open system the heart pumps blood out into an open area where the blood just flows over the different body parts and then comes back to the heart on its own.  An open circulatory system is extremely inefficient and a lower form of evolution.
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The heart is what pumps blood throughout the body, keeping all organs functioning. Blood flows to the body through arteries and blood flows back to the heart through veins. Its all one big system - the circulatory system.
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The cardiovascular system is a closed system, meaning that blood remains inside the vessels no matter how small they are.  The process of diffusion drives oxygen, carbon dioxide, wastes and nutrients between the tissues and the blood inside the blood vessels-blood just goes around the body.  Humans have a 4-chambered heart: 2 ventricles and 2 atria (sing: atrium).  The atria receive blood and the ventricles "expel" the blood (pumps the blood away from the heart).  You can partition the heart into two sides (left and right), each with its own ventricle and atrium.   One side is for the systemic circulation (to the body) and the other is for the pulmonary circulation (to the lungs).  Blood (deoxygenated) from the body collects in the right atrium, which passes the blood to the right ventricle, which relays the blood to the pulmonary arteries (arteries to the lungs) to get oxygen and expel carbon dioxide.  Once the blood in the lungs acquires oxygen, it passes to the pulmonary veins and into the left atrium.  Then, the blood goes into the left ventricle and is pumped into the aorta (think of it as the largest artery in the body or like in the water supply, the main tube of water where all of the other tubes originate). From the aorta it goes to the arteries and then to the arterioles and the capillary networks (where gas exchange occurs).  After being depleted of oxygen, it goes to the venules to the veins then to the vena cavae and back into the right atrium and it goes around again. :-)
1118676
lizards = frogs\nfrogs = lizards
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. Structure and Functions of Blood Vessels \n  Structure Functions \nArteries The walls (outer structure) of arteries contain smooth muscle fibre that contract and relax under the instructions of the sympathetic nervous system.\n   Transport blood away from the heart;\n \n  Transport oxygenated blood only (except in the case of the pulmonary artery).\n \n \n \nArterioles Arterioles are tiny branches of arteries that lead to capillaries. These are also under the control of the sympathetic nervous system, and constrict and dialate, to regulate blood flow.\n   Transport blood from arteries to capillaries;\n \n  Arterioles are the main regulators of blood flow and pressure.\n \n \n \nCapillaries Capillaries are tiny (extremely narrow) blood vessels, of approximately 5-20 micro-metres \n(one micro-metre = 0.000001metre) diameter.\nThere are networks of capillaries in most of the organs and tissues of the body. These capillaries are supplied with blood by arterioles and drained by venules. Capillary walls are only one cell thick (see diagram), which permits exchanges of material between the contents of the capillary and the surrounding tissue. \n   Function is to supply tissues with components of, and carried by, the blood, and also to remove waste from the surrounding cells ... as opposed to simply moving the blood around the body (in the case of other blood vessels);\n \n  Exchange of oxygen, carbon dioxide, water, salts, etc., between the blood and the surrounding body tissues.\n \n \n \nVenules Venules are minute vessels that drain blood from capillaries and into veins. Many venules unite to form a vein.\n   Drains blood from capillaries into veins, for return to the heart\n \n \n \nVeins The walls (outer structure) of veins consist of three layers of tissues that are thinner and less elastic than the corresponding layers of aerteries.\nVeins include valves that aid the return of blood to the heart by preventing blood from flowing in the reverse direction.\n   Transport blood towards the heart;\n \n  Transport deoxygenated blood only (except in the case of the pulmonary vein).
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Frog has 3-chambers. A humam has 4-chambers and the blood w/ o2 don't mix w/ the blood w/ c!!
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Frogs do not have anything that is watertight. Their skin is so porous that water will enter their butts rapidly through osmosis.
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arteries carry blood AWAY from the heart, most of the time they carry O2 rich blood but in the case of pulimanry artieries it carrys O2 poor blood to the lungs\nveins carry blood TOO the heart, viens also have little valves in them to prevent backflow of the blood.\ncapalaries are the way O2 from the blood is transfered to cells. capalariies r VERY VERY VERY small and connect arteries to viens
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wouldn't teh functions of the systems be the same for every organisms.  for example the respiratory system is for breathing in both cows and humans and probably for the toad as well.  the circulatory system is for circulating blood in every organsim.  the excretory system extrects toxins and metabolic wastes and the nervous system allows for cordiation of muscles and autonomic behaviors as well as cognitive thinking.  \n\nhowever the real functions of all these organs is SURVIVAL.  SURVIVAL is the driving force of life and you are kidding yourself if you think otherwise.
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Yes they do. In fact, all insects have hearts but they sure don't look like our big mammalian hearts. A mosquito's heart is a long, skinny, fragile tube that runs along its back, starting near the aNnus', to the chest cavity (the thorax). The tube actually extends to its head but only the abdomen part has muscles to contract and is called the heart.\nA bug's heart contracts (as ours does) to squeeze green (or colorless) blood forward through the heart from chamber to chamber toward the thorax. There the heart simplifies into a plain tube (the aorta) that carries the blood (called hemolymph) to the head. The blood sloshes around in the head, bathing the brain and organs. When each chamber of the heart relaxes, valves open and blood rushes into the heart from the body cavity — but not via blood vessels. \n\nThe blood circulates freely in the body cavity making direct contact with internal tissues and organs. It delivers nutrients, salts, and hormones and whisks away wastes with each heartbeat.\n\nAnuradha
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hey i am not sure whether this is the right answer....but it was worth a try....\n\n \nRana pipiens, also known as the northern leopard frog, is a very important frog in the ecosystem. The northern leopard frog is a key animal in the food web. Frogs are more important to human survival and our current way of life than you may think! Frogs are so important that ecologists consider them to be bioindicators. In other words, scientists consider the health of a frog population to be a reflection of the health of the entire ecosystem (Encarta, 2001).\n\nDistribution\nThe northern leopard frog, R. pipiens, is common in North America, inhabiting twenty-six states and much of Canada (see adjacent map).\n\nHabitat\nRana pipiens live in a wide range of habitat, from open water and marshes to deserts and mountains (Frogs.org, 2000-2001).\n\nPhysical Characteristics\nThe northern leopard frog is medium in size, averaging from two to five inches long. They are green, brown, or both and have large dark irregular spots covering the dorsal part of their body (NPWRC, 2001). The skin covering R. pipiens is moist and smooth, and contains glands that secrete mucus in order to keep the skin from drying out. Northern leopard frogs also have glands in their skin that secrete poisons, which are strong enough to help them escape from their predators but are not harmful to humans (Encarta, 2001). Rana pipiens have eyes that are very keen, helping them not only capture prey but also to identify danger in their surroundings (Encarta, 2001). The northern leopard frog also has very powerful hind legs which are the main source of power in swimming and jumping. Also useful in swimming are the frog's webbed hind feet (Frog, 2001).\n\nFood and Feeding\nThe diets of tadpoles and froglets differ from those of adult R. pipiens, with the young consuming herbivory such as algae as well as microscopic animals. Adults feed largely on insects, but also slugs, snails, and smaller vertebrates such as chorus frogs (Harding 156-157 and Donegan, 1996).\n\nRelationship to other organisms in the ecosystem\nRana pipiens are common prey of birds such as herons, reptiles such as snakes, and mammals (including humans) (Donegan, 1996). Rana pipiens play an important role to humans. Besides being a source of food, frogs are used at every stage in their life for scientific study (Donegan, 1996). Furthermore, frogs play a key role in integrative pest management, eating agriculturally destructive insects.\n\nReproduction\nCopulation occurs in the water between March and June. The females release eggs while swimming and the male, who attaches himself to the female with specialized thumbs, fertilizes the eggs. The fertilized eggs are then attached to either underwater plant material or simply placed on the bottom of the pond (Frogs.org, 2001). Each female lays up to 3,000 eggs, which hatch 10-20 days after fertilization (Rasmussen, 2001).\n\nDevelopment and Lifespan\nThe frog life cycle (shown to the left) is fairly simple. The frogs begin their lives as eggs, which are laid in clumps. When the eggs hatch the baby frogs are tadpoles and do not have limbs or lungs, like the adult frog. The tadpole undergoes metamorphosis, growing hind legs first, then front legs, and at the same time, developing a well defined head. The gills are replaced with lungs as the froglet adapts to life on land. On land the frog continues to lose its tail and grow in size. Rana pipiens reach sexual maturity in two or three years (Encarta, 2001).\n\nBehavior\nRana pipiens are mostly nocturnal. Rana pipiens travel far distances away from water, but they must return to breed. In order to escape predators the northern leopard frog leaps into the water and buries itself in the mud or, if on land, takes several jumps into the air and then dives under vegetation for cover (Harding, 157). During the winter months northern leopard frogs hibernate.\n\nCommunication\nThe male northern leopard frog uses his croak to att
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A frog is compleately covered by a soft, thin and moist layer of skin make of two very important layers, the epidermis and the dermis.\nIt does not really protect the frog in any way but, it helps in the process of respiration. Oxygen can actually pass through a frog’s skin, which then enters into their blood.\nFrogs dont only breathe though their skin, some adult frogs have two sac-like lungs.\nWhen a frog is sumerged underwater, its respiration takes place through their skin only.\nThere are many blood vessels that run throughout the frog’s skin. Oxygen can actually pass through it, therefore, it directly enters into the blood. Oxygen can be gotten from water too.