1. Free-living flatworms:
* Predatory: Many free-living flatworms are carnivorous, feeding on small invertebrates like nematodes, rotifers, and other worms. They use a muscular pharynx to suck in their prey.
* Scavengers: Some free-living flatworms scavenge on dead organic matter, playing a role in decomposition.
* Parasitic: Some free-living flatworms are parasitic, but they often live on or within other invertebrates.
2. Parasitic flatworms:
* Endoparasites: These flatworms live inside their hosts. They feed on the host's tissues or digested food.
* Intestinal parasites: These live in the intestines of their hosts, absorbing nutrients from the food being digested. Examples include tapeworms and flukes.
* Tissue parasites: These flatworms live within the tissues of their host. Examples include liver flukes and blood flukes.
* Ectoparasites: These flatworms live on the surface of their hosts, often feeding on blood or fluids. Examples include skin flukes and monogeneans.
How they eat:
* Pharynx: Most flatworms have a muscular pharynx that they can extend out to capture prey or suck in food.
* Digestive system: The digestive system of a flatworm is simple, often consisting of a single opening that acts as both the mouth and anus. They lack a specialized stomach or intestines.
* Absorption: Flatworms absorb nutrients through their skin or digestive tract.
Key characteristics of flatworm feeding:
* Lack of specialized mouthparts: Most flatworms lack specialized mouthparts for chewing or grinding.
* Simple digestive system: Their digestive system is often a single tube, with food entering and waste exiting through the same opening.
* Extracellular digestion: Flatworms release enzymes that break down their food outside of their bodies, making it easier to absorb.
Interesting fact: Some parasitic flatworms, like tapeworms, absorb nutrients directly from their host's intestines without needing to digest their own food.
In conclusion, flatworms have a variety of feeding strategies depending on their lifestyle. From hunting prey to absorbing nutrients from their host, they have adapted to survive in a wide range of environments.