The three main parts of the circ. system are heart, blood and blood vessels. The heart pumps blood and it goes through arteries to cells everywhere in your body. Then your veins bring it back to your...
There are two main types of circulatory systems:
1. Open
2. Closed
In an open circulatory system, blood mixes with internal organs directly. Organisms with this type of system do not have a true...
The heart. It circulates oxygenated blood from the lungs to the rest of the body and give oxygen to de-oxygenated blood by sending it to the lungs. The heart has four parts, the left atria, the right...