1. The right side of the mammalian heart pumps blood to the LUNGS. Here it absorbs OXYGEN and is now called OXYGENATED blood.
The gas, CARBON DIOXIDE is removed from the blood in the lungs. The blood returns to the LEFT side of the heart and from here it is pumped to the BODY TISSUES where it gives up its OXYGEN and is now called DEOXYGENATED blood. It passes back to the LEFT side of the heart in VEINS
2. Single Circulation -> The blood only passes through the heart once
Double Circulation -> The blood passes through the heart twice
3. Made of myocardium (thick muscle), four-chambered separated by valves, cardiac muscle is oxygenated via cornary ateries + veins, transports blood carrying oxygen + nutrients to the body's tissues
