Answer:
The circulatory system of annelids is a closed circulatory system. This means that the blood is always contained within the vessels and never comes into contact with the body tissues. The heart is located in the center of the body and pumps blood to the gills, where it is oxygenated. From the gills, the blood flows through the body and back to the heart.
Step-by-step explanation:
The circulatory system of annelids is a closed circulatory system. This means that the blood is always contained within the vessels and never comes into contact with the body tissues. The heart pumps the blood through the vessels to the tissues and then back to the heart. The blood vessels are arranged in a series so that the blood can flow in one direction only.There are three main types of circulation in annelids: open, closed, and mixed. Closed circulation is found in all earthworms and some leeches. In closed circulation, the blood is confined to blood vessels and does not come into direct contact with body tissues. The advantage of this type of circulation is that it allows for more efficient gas exchange between the blood and the body tissues. Mixed circulation is found in some leeches and some earthworms. In mixed circulation, the blood flows through both blood vessels and body tissues. This allows for more efficient gas exchange between the blood and body tissues, but at the expense of a more complex circulatory system.