The heart and lungs

The heart has 4 chambers and it is the size of your fist. your heart is on the right side but some people think it is on the left and it has 4 valves.

your heart is located by your chest under your rib cage. The blood carries oxygen. Heart attacks can be caused by scar tissue to form amgost the normal heart tissue, this then can lead to further heart problem's or even heart failure. 

The lungs help us to breathe and if we dint have lungs we wouldn't be able to breathe. The lungs are part of our respiratory system the system is there so we can breathe to circulate the oxygen into the body. surprising, adults lungs approximately contain 2,400 kilometres of airways and have a total surface area of about 70 - 700 square meters this is almost the size of a half a tennis court- all packed into a chest.