1. Heart
The Heart Description: Your heart is about the size of your fist. ... The heart is a muscle; it acts like a small pump. ... The middle of the heart is called myocardium. ... • Coronary Heart Disease: It is the most common heart disease in the US today. ... Sometimes the heart will skip a beat, or it might be a continuous slow or fast heart rate. ...
- Word Count: 441
- Approx Pages: 2
- Grade Level: High School