Respuesta :
The correct option is (A) None of their cells are far removed from the gastrovascular cavity or from the external environment.
Why Planarians lack respiratory and circulatory system?
- Although planarians don't appear to have any respiratory or circulatory systems, they do have muscles that line the interior of the body in circular, diagonal, and longitudinal patterns.
- The flatworm doesn't have lungs, therefore it doesn't require a particular circulatory system like a human does to move oxygen throughout its body.
- Through its skin, the flatworm merely diffuses oxygen. Anywhere that it would want oxygen, this happens.
- None of the cells of planarians are a great distance from the gastrovascular cavity or the outside environment, hence they lack specialized respiratory and circulatory systems.
Learn more about the Planaria with the help of the given link:
https://brainly.com/question/1850129
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