The West is blinking in disbelief â Vladimir Putin just invaded Ukraine. German diplomats, French Eurocrats and American pundits are all stunned.
The  circulatory system is the body's transport system. It is made up of a group of organs that transport blood throughout the body. The heart pumps the blood and the arteries and veins transport it. Oxygen-rich blood leaves the left side of the heart and enters the biggest artery, called the aorta.
The human body is made up of several organ systems that all work together as a unit to make sure the body keeps functioning. There are ten major organ systems in the body, each of which plays a different role in helping the body work. This system is made up of the heart, blood, blood vessels, and lymphatics. It is the bodyâs delivery system, concerned with circulating blood to deliver oxygen and nutrients to every part of the body. The purpose of the digestive system is to turn the food you eat into something useful for the body.