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 11 organ systems that work with one another (interdependantly). These systems include the integumentary system, skeletal system, muscular system, lymphatic system, respiratory system, digestive system, nervous system, endocrine system, cardiovascular system, urinary system, and reproductive systems. We will briefly discuss the major functions of each organ system below.