1) In annelids, the digestive system is through, and in free-living flatworms, the digestive system is closed
2) Ringworms have a circulatory system that was not present in flatworms
3) In annelids, unlike flatworms, a secondary body cavity appeared, filled with liquid, which is involved in the metabolism and creates support when moving
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.