Question

Why is a blood system unnecessary in either free-living or parasitic flatworms

Answer 1

Flatworms have no body cavity other than the gut (and the smallest free-living forms may even lack that!) and lack an anus; the same pharyngeal opening both takes in food and expels waste. ... Flukes, like other parasitic flatworms, have complex life cycles often involving two or more host organisms.

Answer 2

Answer:

The lungs are absent  in the flatworm, so a blood system is not important in parasites.

Explanation:

• Platyhelminth is also referred to as a flatworm which are soft-bodies and flattened invertebrates.
• Examples of parasites are tapeworms and liver flukes.
• They do not digest their meals due to absence of a digestive system.
• When the muscles in the top of stomach contract, they easily absorb the nutrients from the food that humans eat, sucked them into their bodies, then gobbled them up.
• The parasite does not contain blood vessels and has a opening in its body that transfers oxygen throughout the body.

To learn more about flatworm, visit:

https://brainly.in/question/49837369

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https://brainly.in/question/36087803

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