How many heart does an earthworm have?

While it is commonly believed that the more complex an organism, the more complex the arrangement or organization of internal organs, earthworms are different. Though not as complex as humans, an earthworm has five different hearts. The hearts, however, referred to as aortic arches, are not referred to as true hearts, when compared to the structure and properties of those of other organisms.

Strictly speaking, an earthworm has about ten different “hearts”, but only five of those ten perform the function of pumping blood throughout the body of the earthworm.

Biology

3 years ago

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Math Calculus — AID—

Total time spent: 4 hours 15 minutes (it is equivalent to 255 minutes). Let the flight time from Paris to Glasgow be X. Then the flight time from Glasgow to Paris will be (X+10). We have an equation with one unknown variable: X + 45 + (X+10) = 255 ⇒ X = 100 So the […]

What were the typical crafts for Maya?

Mayans are well-known as great pottery makers. They did not use the pottery wheel. However,the tecnique they used was coiling consecutive rings of clay on top of each other and smoothing the surface by hand. Also, they were good when it came to working with stone – stone craving is another important craft of Maya. Many […]

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Cigarette smoking causes emphysema.

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