What organ systems are developed in flatworms?

In the process of evolution, real tissues, organs and organ systems first appeared in Flatworms, a typical representative of which is the white planarian.

Their organ systems:

– musculoskeletal, formed by skin and muscles;

– digestive (mouth – pharynx – intestines);

– excretory, consists of excretory tubes that open with pores in the skin;

– nervous (2 nerve nodes, 2 nerve trunks and transverse nerves);

– genital (hermaphrodites, since in one body there are both testes and ovaries).