Last weak I read this topic in a magazine , and I like it coz has new data 4 me , after that I decide to write it .. jst 4 knowledge
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crocodiles may not cry real tears. but they do have special heart . like mammal and bird heart. crocodile's heart is muscle that pumps blood. one side of the heart sends blood that is full of oxygen out to most of the body. the other side pulls blood back toward the lungs to give it an oxygen refill
But crocodile (and alligator) hearts have an extra valve that mammal and bird hearts do not have . The extra valve is flap that the animal can close in order to keep blood from flowing toward lungs. This means that the blood goes right back into the body instead
Although scientists have know about the crocodile heart's extra valve for many years, they haven't known what it was for. some scientists thought that it might help crocodiles and alligators stay underwater longer, making them better, more deadly hunters
Now, scientists have anew idea about what crocodile's heart can do. By studying captive alligators, scientists discovered that the extra valve can reroute some of the blood normally pumped to its lungs to its stomach instead. this diversion lasts about the same amount of time that it takes an alligator to digest a big meal[
To see if the valve is really connected to digestion , the scientists used surgery to close the valve in some captive alligators but left it working in others. they then fed each alligator a meal of hamburger meat and an oxtail bone. Alligators with a working valve digested the tough meal quicker
Blood returning from the body to the heart has extra carbon dioxide . carbon dioxide is also a building block of stomach acid . which helps digest food. so, when blood rich with carbon dioxide goes to the stomach instead of the lungs, it can aid digestion
Whether it helps alligators and crocodiles pursue their underwater prey or helps them digest it, the heart's special valve does seem to give these hunters a leg up on the competition
But crocodile (and alligator) hearts have an extra valve that mammal and bird hearts do not have . The extra valve is flap that the animal can close in order to keep blood from flowing toward lungs. This means that the blood goes right back into the body instead
Although scientists have know about the crocodile heart's extra valve for many years, they haven't known what it was for. some scientists thought that it might help crocodiles and alligators stay underwater longer, making them better, more deadly hunters
Now, scientists have anew idea about what crocodile's heart can do. By studying captive alligators, scientists discovered that the extra valve can reroute some of the blood normally pumped to its lungs to its stomach instead. this diversion lasts about the same amount of time that it takes an alligator to digest a big meal[
To see if the valve is really connected to digestion , the scientists used surgery to close the valve in some captive alligators but left it working in others. they then fed each alligator a meal of hamburger meat and an oxtail bone. Alligators with a working valve digested the tough meal quicker
Blood returning from the body to the heart has extra carbon dioxide . carbon dioxide is also a building block of stomach acid . which helps digest food. so, when blood rich with carbon dioxide goes to the stomach instead of the lungs, it can aid digestion
Whether it helps alligators and crocodiles pursue their underwater prey or helps them digest it, the heart's special valve does seem to give these hunters a leg up on the competition
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