CIRCULATORY SYSTEM

The circulatory system is made of the heart, blood and blood vessels called arteries, capillaries and veins.  

HEART 💚

The function of heart is pumping blood throughout your body through the blood vessels. Blood delivers oxygen and nutrient to cells and carries away carbon dioxide and other waste materials. 
The heart looks like an upside-down pear. It is almost in the middle of the chest, in the left side and is made of muscle. It is divided into four parts called chambers. It also has four valves that let blood in and out of the chambers. 

Tubes called arteries come out of the heart. Tubes called veins go into the heart.  

It is always beating, day and night. No one can live if their heart stops beating for more than a few minutes. 

BLOOD 

Blood carries food and oxygen to every part of the body because it needs food and oxygen for energy. Big arteries carry the blood to legs and arms. Capillaries are little blood vessels that take blood to the cells.  

VEINS 

Veins are blood vessels that return blood to the heart from other parts of the body.  

The circulatory system circulates through all the body, and is connected with the rest of systems. Digestive and respiratory systems are the most connected with it.