Ask A Scientist

How does the human heart work?

Asked by: Vincent Mancini
School: Maine Endwell Middle School
Grade: 6
Teacher: Kevin Wagstaff
Hobbies/Interests: Baseball, football and basketball
Career Interest: A baseball player for the New York Yankees

Answer from Nikki Austin

Research Assistant, Binghamton University

Research area:
Exercise and Physical Activity, Gerontological Nursing

Ph.D. school:
Enrolled in the Decker School of Nursing PhD program

The heart is a very specialized muscle called the myocardium. Its purpose is to pump blood through the body. If you make a fist with your hand, that is about the size of your heart. Now squeeze your fist once every second. That is about the minimum amount of beats that your heart normally beats every minute of every day, whether awake or asleep. Your heart is able to generate electrical impulses that make the heart beat. The heart is mostly a hollow muscle with four chambers. The two on the top are called the atria. They receive blood and contract to squeeze the blood into the lower chambers or ventricles. The ventricles then contract sending blood out of the heart. There are special valves between each of the chambers of the heart to keep blood going in the right direction. If you put your ear on someone's chest and listen to the heart beating, what you actually hear is the valves in the heart snapping shut to keep the blood from flowing backwards through the heart. Sometimes people have leaky valves, or valves that become stiff and don't work. Those valves may be replaced through a heart operation. When you feel a pulse, you feel the pressure generated by the heart to move blood through your arteries. It is very important to keep the blood pumping because we need the oxygen for the cells in our bodies to work properly. The cells keep the oxygen, use it, and get rid of it in the form of carbon dioxide. The right side of the heart pumps blood that is low on oxygen to the lungs. In the lungs the blood picks up oxygen and gets rid of carbon dioxide. The blood then goes into the left side of the heart, where it is pumped to the body. All muscles in your body, including the heart, need the blood and oxygen that are delivered through the arteries. The heart receives its blood, oxygen, and nutrients, through the arteries that are called coronary arteries that are actually located on the outside of the heart. They may become clogged with a substance called cholesterol, or a blood clot. When the arteries are too clogged to let blood through, the heart will begin to have serious problems such as chest pain or a heart attack. Both of those are emergencies requiring immediate treatment in order to keep the muscle from being damaged. Your heart needs exercise in order to work properly. When you exercise, play sports, or even walk at a fast pace, you are exercising the muscles in your body and your heart. When you choose to eat foods that are low in fat and cholesterol, you help to keep your arteries from being clogged. Take care of your heart now to prevent problems later in your life! To learn more about heart health and research currently underway in the greater Binghamton area call the O'Connor Office of Rural Health Studies at 1- 866-205-8120 or visit

Last Updated: 3/1/17