The structure of the heart
Heart DiagramThe heart is made up of three layers:
Pericardium – thin outer protective sack
Myocardium – specialised cells making up the thick muscular wall
Endocardium – thin inner lining of the heart
Inside the heart there are four chambers – two on the left side and two on the right
The two small upper chambers are called the atria
The two larger lower chambers are called the ventricles
Heart DiagramThe heart is made up of three layers:
Pericardium – thin outer protective sack
Myocardium – specialised cells making up the thick muscular wall
Endocardium – thin inner lining of the heart
Inside the heart there are four chambers – two on the left side and two on the right
The two small upper chambers are called the atria
The two larger lower chambers are called the ventricles



