Circulatory System (Day 2)

The circulatory system also known as the cardiovascular system, is the body system that moves blood around the body. The heart and all blood vessels make up the circulatory system.

Blood vessels that take blood away from the heart are arteries. Arteries get smaller as they go away from the heart. The smaller arteries that connect to the capillaries, are called arterioles.

The aorta is the largest artery in the body. The aorta begins at the top of the left ventricle, the heart's muscular pumping chamber. The heart pumps blood from the left ventricle into the aorta through the aortic valve.

Blood vessels that take blood towards the heart are veins. Veins get bigger as they go towards the heart. The smallest veins are called venules.

Capillaries go between arteries and veins. Capillaries are quite thin, hence the name which comes from the Latin capillus meaning "hair."

So blood moves: 

heart→artery→arteriole→capillary

→venule→vein→heart.

This is called circulation.

There are two different circulations in the circulatory system. The systemic circulation is how blood goes to most of the body. The pulmonary circulation is how blood goes through the lungs. (Pulmonary means ¨about the lungs¨). This is how it works in mammals, including humans. Circulatory systems of other vertebrates differ somewhat. Invertebrates are very different.

Complete the Cardiovascular System Lesson Activity from iLearn Edmentum